From 2e8cad7d8efb941de46198038b1600c0ceb6baf5 Mon Sep 17 00:00:00 2001
From: Progi1984 <progi1984@gmail.com>
Date: Fri, 1 Dec 2023 15:14:09 +0100
Subject: [PATCH] Fixed CI

---
 .php-cs-fixer.dist.php                        | 231 +++++-
 docs/changes/1.1.0.md                         |  10 +-
 samples/Sample_03_Image.php                   |   2 +-
 samples/Sample_05_Chart.php                   |  24 +-
 samples/Sample_06_Fill.php                    |   4 +
 samples/Sample_07_Border.php                  |   4 +
 samples/Sample_11_Shape.php                   |   8 +-
 samples/Sample_15_Background.php              |   4 +-
 samples/Sample_Header.php                     |  28 +-
 samples/index.php                             |   6 +-
 src/PhpPresentation/AbstractShape.php         |  40 +-
 src/PhpPresentation/Autoloader.php            |   1 -
 src/PhpPresentation/ComparableInterface.php   |   3 +-
 src/PhpPresentation/DocumentLayout.php        |  13 +-
 src/PhpPresentation/DocumentProperties.php    |  24 +-
 .../Exception/DirectoryNotFoundException.php  |   1 -
 .../FeatureNotImplementedException.php        |   1 -
 .../Exception/FileCopyException.php           |   1 -
 .../Exception/FileNotFoundException.php       |   1 -
 .../Exception/FileRemoveException.php         |   1 -
 .../Exception/InvalidClassException.php       |   1 -
 .../Exception/InvalidFileFormatException.php  |   1 -
 .../Exception/InvalidParameterException.php   |   1 -
 .../Exception/OutOfBoundsException.php        |   1 -
 .../Exception/PhpPresentationException.php    |   1 -
 ...ShapeContainerAlreadyAssignedException.php |   1 -
 .../UnauthorizedMimetypeException.php         |   2 -
 .../Exception/UndefinedChartTypeException.php |   1 -
 src/PhpPresentation/GeometryCalculator.php    |   1 -
 src/PhpPresentation/HashTable.php             |   1 -
 src/PhpPresentation/IOFactory.php             |  22 +-
 src/PhpPresentation/PhpPresentation.php       |   9 +-
 .../PresentationProperties.php                |  27 +-
 src/PhpPresentation/Reader/ODPresentation.php |  59 +-
 src/PhpPresentation/Reader/PowerPoint2007.php |  90 +--
 src/PhpPresentation/Reader/PowerPoint97.php   | 198 ++---
 .../Reader/ReaderInterface.php                |   1 -
 src/PhpPresentation/Reader/Serialized.php     |  14 +-
 src/PhpPresentation/Shape/AbstractGraphic.php |   3 +-
 src/PhpPresentation/Shape/AutoShape.php       |  27 +-
 src/PhpPresentation/Shape/Chart.php           |  27 +-
 src/PhpPresentation/Shape/Chart/Axis.php      | 132 +---
 src/PhpPresentation/Shape/Chart/Gridlines.php |   1 -
 src/PhpPresentation/Shape/Chart/Legend.php    |   9 +-
 src/PhpPresentation/Shape/Chart/Marker.php    |  17 -
 src/PhpPresentation/Shape/Chart/PlotArea.php  |  12 +-
 src/PhpPresentation/Shape/Chart/Series.php    |  45 +-
 src/PhpPresentation/Shape/Chart/Title.php     |   7 +-
 .../Shape/Chart/Type/AbstractType.php         |   3 +-
 .../Shape/Chart/Type/AbstractTypeBar.php      |   6 -
 .../Shape/Chart/Type/AbstractTypeLine.php     |  11 +-
 .../Shape/Chart/Type/AbstractTypePie.php      |   1 -
 src/PhpPresentation/Shape/Chart/Type/Area.php |   1 -
 src/PhpPresentation/Shape/Chart/Type/Bar.php  |   1 -
 .../Shape/Chart/Type/Bar3D.php                |   1 -
 .../Shape/Chart/Type/Doughnut.php             |   1 -
 src/PhpPresentation/Shape/Chart/Type/Line.php |   1 -
 src/PhpPresentation/Shape/Chart/Type/Pie.php  |   1 -
 .../Shape/Chart/Type/Pie3D.php                |   1 -
 .../Shape/Chart/Type/Radar.php                |   3 +-
 .../Shape/Chart/Type/Scatter.php              |   1 -
 src/PhpPresentation/Shape/Chart/View3D.php    |   5 +-
 src/PhpPresentation/Shape/Comment.php         |   7 +-
 src/PhpPresentation/Shape/Comment/Author.php  |   1 -
 .../Shape/Drawing/AbstractDrawingAdapter.php  |   1 -
 src/PhpPresentation/Shape/Drawing/Base64.php  |  18 +-
 src/PhpPresentation/Shape/Drawing/File.php    |  10 +-
 src/PhpPresentation/Shape/Drawing/Gd.php      |   9 +-
 src/PhpPresentation/Shape/Drawing/ZipFile.php |  12 +-
 src/PhpPresentation/Shape/Group.php           |  13 -
 src/PhpPresentation/Shape/Hyperlink.php       |  33 +-
 src/PhpPresentation/Shape/Line.php            |   1 -
 src/PhpPresentation/Shape/Media.php           |   4 +-
 src/PhpPresentation/Shape/Placeholder.php     |   3 +-
 src/PhpPresentation/Shape/RichText.php        | 121 +--
 .../Shape/RichText/BreakElement.php           |   1 -
 .../Shape/RichText/Paragraph.php              |  52 +-
 src/PhpPresentation/Shape/RichText/Run.php    |   5 +-
 .../Shape/RichText/TextElement.php            |  11 +-
 .../Shape/RichText/TextElementInterface.php   |   1 -
 src/PhpPresentation/Shape/Table.php           |  18 -
 src/PhpPresentation/Shape/Table/Cell.php      |  11 +-
 src/PhpPresentation/Shape/Table/Row.php       |  21 +-
 .../ShapeContainerInterface.php               |   1 -
 src/PhpPresentation/Slide.php                 |  16 +-
 .../Slide/AbstractBackground.php              |   1 -
 src/PhpPresentation/Slide/AbstractSlide.php   |  24 +-
 src/PhpPresentation/Slide/Animation.php       |   1 -
 .../Slide/Background/Color.php                |   5 +-
 .../Slide/Background/Image.php                |   9 +-
 .../Slide/Background/SchemeColor.php          |   5 +-
 src/PhpPresentation/Slide/Iterator.php        |   9 +-
 src/PhpPresentation/Slide/Layout.php          |   1 -
 src/PhpPresentation/Slide/Note.php            |   9 +-
 src/PhpPresentation/Slide/SlideLayout.php     |  13 +-
 src/PhpPresentation/Slide/SlideMaster.php     |  29 +-
 src/PhpPresentation/Slide/Transition.php      |  19 +-
 src/PhpPresentation/Style/Alignment.php       |  21 +-
 src/PhpPresentation/Style/Border.php          |  31 +-
 src/PhpPresentation/Style/Borders.php         |   3 +-
 src/PhpPresentation/Style/Bullet.php          |   7 +-
 src/PhpPresentation/Style/Color.php           |  13 +-
 src/PhpPresentation/Style/ColorMap.php        |   1 -
 src/PhpPresentation/Style/Fill.php            |  27 +-
 src/PhpPresentation/Style/Font.php            |  45 +-
 src/PhpPresentation/Style/Outline.php         |   1 -
 src/PhpPresentation/Style/SchemeColor.php     |   1 -
 src/PhpPresentation/Style/Shadow.php          |   9 +-
 src/PhpPresentation/Style/TextStyle.php       |   7 +-
 .../Writer/AbstractDecoratorWriter.php        |   4 -
 src/PhpPresentation/Writer/AbstractWriter.php |  11 +-
 src/PhpPresentation/Writer/ODPresentation.php |  19 +-
 .../AbstractDecoratorWriter.php               |   1 -
 .../Writer/ODPresentation/Content.php         |  91 ++-
 .../Writer/ODPresentation/Meta.php            |   8 +-
 .../Writer/ODPresentation/MetaInfManifest.php |   4 -
 .../Writer/ODPresentation/Mimetype.php        |   4 -
 .../Writer/ODPresentation/ObjectsChart.php    |  35 +-
 .../Writer/ODPresentation/Pictures.php        |   4 -
 .../Writer/ODPresentation/Styles.php          |  12 +-
 .../ODPresentation/ThumbnailsThumbnail.php    |   3 +-
 src/PhpPresentation/Writer/PowerPoint2007.php |  16 +-
 .../AbstractDecoratorWriter.php               |   8 +-
 .../Writer/PowerPoint2007/AbstractSlide.php   |  87 ++-
 .../Writer/PowerPoint2007/CommentAuthors.php  |   1 -
 .../Writer/PowerPoint2007/ContentTypes.php    |   2 +-
 .../Writer/PowerPoint2007/DocPropsApp.php     |   1 -
 .../Writer/PowerPoint2007/DocPropsCore.php    |   5 +-
 .../Writer/PowerPoint2007/DocPropsCustom.php  |   6 +-
 .../PowerPoint2007/DocPropsThumbnail.php      |   1 -
 .../Writer/PowerPoint2007/PptCharts.php       |  54 +-
 .../Writer/PowerPoint2007/PptComments.php     |   7 -
 .../Writer/PowerPoint2007/PptMedia.php        |   4 -
 .../Writer/PowerPoint2007/PptPresProps.php    |   4 -
 .../Writer/PowerPoint2007/PptPresentation.php |   4 -
 .../Writer/PowerPoint2007/PptSlideLayouts.php |   6 +-
 .../Writer/PowerPoint2007/PptSlideMasters.php |   8 +-
 .../Writer/PowerPoint2007/PptSlides.php       |   5 +-
 .../Writer/PowerPoint2007/PptTableProps.php   |   4 -
 .../Writer/PowerPoint2007/PptTheme.php        |   6 +-
 .../Writer/PowerPoint2007/PptViewProps.php    |   4 -
 .../Writer/PowerPoint2007/Relationships.php   |   4 +-
 src/PhpPresentation/Writer/Serialized.php     |   9 +-
 .../Writer/WriterInterface.php                |   3 +-
 .../Tests/AbstractShapeTest.php               | 147 ++--
 .../PhpPresentation/Tests/AutoloaderTest.php  |   5 +-
 .../Tests/DocumentLayoutTest.php              |  75 +-
 .../Tests/DocumentPropertiesTest.php          |  99 ++-
 tests/PhpPresentation/Tests/HashTableTest.php |  43 +-
 tests/PhpPresentation/Tests/IOFactoryTest.php |   7 +-
 .../Tests/PhpPresentationTest.php             |  33 +-
 .../Tests/PresentationPropertiesTest.php      |  97 ++-
 .../Tests/Reader/ODPresentationTest.php       | 653 ++++++++--------
 .../Tests/Reader/PowerPoint2007Test.php       | 711 +++++++++---------
 .../Tests/Reader/PowerPoint97Test.php         |  35 +-
 .../Tests/Reader/SerializedTest.php           |   3 +-
 .../Tests/Shape/AbstractGraphicTest.php       |  85 ++-
 .../Tests/Shape/AutoShapeTest.php             |  27 +-
 .../Tests/Shape/Chart/AxisTest.php            | 177 +++--
 .../Tests/Shape/Chart/GridlinesTest.php       |   9 +-
 .../Tests/Shape/Chart/LegendTest.php          |  91 ++-
 .../Tests/Shape/Chart/MarkerTest.php          |  21 +-
 .../Tests/Shape/Chart/PlotAreaTest.php        |  47 +-
 .../Tests/Shape/Chart/SeriesTest.php          | 171 +++--
 .../Tests/Shape/Chart/TitleTest.php           |  79 +-
 .../Tests/Shape/Chart/Type/AbstractTest.php   |  27 +-
 .../Tests/Shape/Chart/Type/AreaTest.php       |  19 +-
 .../Tests/Shape/Chart/Type/Bar3DTest.php      |  57 +-
 .../Tests/Shape/Chart/Type/BarTest.php        |  79 +-
 .../Tests/Shape/Chart/Type/DoughnutTest.php   |  37 +-
 .../Tests/Shape/Chart/Type/LineTest.php       |  25 +-
 .../Tests/Shape/Chart/Type/Pie3DTest.php      |  25 +-
 .../Tests/Shape/Chart/Type/PieTest.php        |  19 +-
 .../Tests/Shape/Chart/Type/RadarTest.php      |   3 +-
 .../Tests/Shape/Chart/Type/ScatterTest.php    |  25 +-
 .../Tests/Shape/Chart/View3DTest.php          |  59 +-
 .../PhpPresentation/Tests/Shape/ChartTest.php |  51 +-
 .../Tests/Shape/Comment/AuthorTest.php        |  25 +-
 .../Tests/Shape/CommentTest.php               |  43 +-
 .../Tests/Shape/Drawing/Base64Test.php        |  13 +-
 .../Tests/Shape/Drawing/FileTest.php          |  21 +-
 .../Tests/Shape/Drawing/ZipFileTest.php       |   5 +-
 .../PhpPresentation/Tests/Shape/GroupTest.php |  59 +-
 .../Tests/Shape/HyperlinkTest.php             |  67 +-
 .../PhpPresentation/Tests/Shape/LineTest.php  |  13 +-
 .../PhpPresentation/Tests/Shape/MediaTest.php |  11 +-
 .../Tests/Shape/PlaceholderTest.php           |  20 +-
 .../Tests/Shape/RichText/BreakElementTest.php |  21 +-
 .../Tests/Shape/RichText/ParagraphTest.php    | 107 ++-
 .../Tests/Shape/RichText/RunTest.php          |  33 +-
 .../Tests/Shape/RichText/TextElementTest.php  |  41 +-
 .../Tests/Shape/RichTextTest.php              | 195 +++--
 .../Tests/Shape/Table/CellTest.php            | 105 ++-
 .../Tests/Shape/Table/RowTest.php             |  27 +-
 .../PhpPresentation/Tests/Shape/TableTest.php |  21 +-
 .../Tests/Slide/AbstractSlideTest.php         |  13 +-
 .../Tests/Slide/AnimationTest.php             |  23 +-
 .../Tests/Slide/Background/ColorTest.php      |  11 +-
 .../Tests/Slide/Background/ImageTest.php      |  33 +-
 .../Slide/Background/SchemeColorTest.php      |  11 +-
 .../Tests/Slide/IteratorTest.php              |  15 +-
 .../PhpPresentation/Tests/Slide/NoteTest.php  |  29 +-
 .../Tests/Slide/SlideLayoutTest.php           |  17 +-
 .../Tests/Slide/SlideMasterTest.php           |  41 +-
 .../Tests/Slide/TransitionTest.php            |  61 +-
 tests/PhpPresentation/Tests/SlideTest.php     |  91 ++-
 .../Tests/Style/AlignmentTest.php             | 133 ++--
 .../Tests/Style/BorderTest.php                |  55 +-
 .../Tests/Style/BordersTest.php               |  21 +-
 .../Tests/Style/BulletTest.php                |  67 +-
 .../Tests/Style/ColorMapTest.php              |  21 +-
 .../PhpPresentation/Tests/Style/ColorTest.php |  59 +-
 .../PhpPresentation/Tests/Style/FillTest.php  |  43 +-
 .../PhpPresentation/Tests/Style/FontTest.php  | 193 +++--
 .../Tests/Style/OutlineTest.php               |  17 +-
 .../Tests/Style/ShadowTest.php                |  81 +-
 .../Tests/Style/TextStyleTest.php             | 131 ++--
 .../Tests/Writer/AbstractWriter.php           |   3 -
 .../Tests/Writer/AbstractWriterTest.php       |   9 +-
 .../Writer/ODPresentation/ContentTest.php     |  58 +-
 .../ODPresentation/MetaInfManifestTest.php    |   1 -
 .../Tests/Writer/ODPresentation/MetaTest.php  |   6 +-
 .../ODPresentation/ObjectsChartTest.php       | 229 ++----
 .../Writer/ODPresentation/StylesTest.php      |   6 +-
 .../Tests/Writer/ODPresentationTest.php       |  15 +-
 .../PowerPoint2007/CommentAuthorsTest.php     |   1 -
 .../Writer/PowerPoint2007/DocPropsAppTest.php |   1 -
 .../PowerPoint2007/DocPropsCoreTest.php       |   1 -
 .../PowerPoint2007/DocPropsCustomTest.php     |   1 -
 .../PowerPoint2007/DocPropsThumbnailTest.php  |   1 -
 .../Writer/PowerPoint2007/PptChartsTest.php   |  33 +-
 .../Writer/PowerPoint2007/PptCommentsTest.php |   1 -
 .../Writer/PowerPoint2007/PptMediaTest.php    |   1 -
 .../PowerPoint2007/PptPresPropsTest.php       |   1 -
 .../PowerPoint2007/PptPresentationTest.php    |   1 -
 .../PowerPoint2007/PptSlideMastersTest.php    |  16 +-
 .../Writer/PowerPoint2007/PptSlidesTest.php   |  51 +-
 .../PowerPoint2007/PptTablePropsTest.php      |   1 -
 .../PowerPoint2007/PptViewPropsTest.php       |   1 -
 .../PowerPoint2007/RelationshipsTest.php      |   1 -
 .../Tests/Writer/PowerPoint2007Test.php       |  17 +-
 .../Tests/Writer/SerializedTest.php           |   9 +-
 .../_includes/PhpPresentationTestCase.php     |  31 +-
 tests/bootstrap.php                           |   5 +-
 244 files changed, 3654 insertions(+), 4142 deletions(-)

diff --git a/.php-cs-fixer.dist.php b/.php-cs-fixer.dist.php
index 532c34a425..dd9be6be69 100644
--- a/.php-cs-fixer.dist.php
+++ b/.php-cs-fixer.dist.php
@@ -6,36 +6,215 @@
     ->setUsingCache(true)
     ->setRiskyAllowed(true)
     ->setRules([
-        '@Symfony' => true,
+        'align_multiline_comment' => true,
         'array_indentation' => true,
-        'cast_spaces' => [
-            'space' => 'single',
-        ],
+        'array_syntax' => ['syntax' => 'short'],
+        'backtick_to_shell_exec' => true,
+        'binary_operator_spaces' => true,
+        'blank_line_after_namespace' => true,
+        'blank_line_after_opening_tag' => true,
+        'blank_line_before_statement' => true,
+        'braces' => true,
+        'cast_spaces' => true,
+        'class_attributes_separation' => ['elements' => ['method' => 'one', 'property' => 'one']], // const are often grouped with other related const
+        'class_definition' => false,
+        'class_keyword_remove' => false, // ::class keyword gives us better support in IDE
         'combine_consecutive_issets' => true,
-        'concat_space' => [
-            'spacing' => 'one',
-        ],
-        'error_suppression' => [
-            'mute_deprecation_error' => false,
-            'noise_remaining_usages' => false,
-            'noise_remaining_usages_exclude' => [],
-        ],
-        'function_to_constant' => false,
+        'combine_consecutive_unsets' => true,
+        'combine_nested_dirname' => true,
+        'comment_to_phpdoc' => false, // interferes with annotations
+        'compact_nullable_typehint' => true,
+        'concat_space' => ['spacing' => 'one'],
+        'constant_case' => true,
+        'date_time_immutable' => false, // Break our unit tests
+        'declare_equal_normalize' => true,
+        'declare_strict_types' => false, // Too early to adopt strict types
+        'dir_constant' => true,
+        'doctrine_annotation_array_assignment' => true,
+        'doctrine_annotation_braces' => true,
+        'doctrine_annotation_indentation' => true,
+        'doctrine_annotation_spaces' => true,
+        'elseif' => true,
+        'encoding' => true,
+        'ereg_to_preg' => true,
+        'escape_implicit_backslashes' => true,
+        'explicit_indirect_variable' => false, // I feel it makes the code actually harder to read
+        'explicit_string_variable' => false, // I feel it makes the code actually harder to read
+        'final_class' => false, // We need non-final classes
+        'final_internal_class' => true,
+        'final_public_method_for_abstract_class' => false, // We need non-final methods
+        'fopen_flag_order' => true,
+        'fopen_flags' => true,
+        'full_opening_tag' => true,
+        'fully_qualified_strict_types' => true,
+        'function_declaration' => true,
+        'function_to_constant' => true,
+        'function_typehint_space' => true,
+        'general_phpdoc_annotation_remove' => ['annotations' => ['access', 'category', 'copyright', 'throws']],
+        'global_namespace_import' => true,
+        'header_comment' => false, // We don't use common header in all our files
+        'heredoc_indentation' => false, // Requires PHP >= 7.3
+        'heredoc_to_nowdoc' => false, // Not sure about this one
+        'implode_call' => true,
+        'include' => true,
+        'increment_style' => true,
+        'indentation_type' => true,
+        'is_null' => true,
+        'line_ending' => true,
+        'linebreak_after_opening_tag' => true,
+        'list_syntax' => ['syntax' => 'short'],
+        'logical_operators' => true,
+        'lowercase_cast' => true,
+        'lowercase_keywords' => true,
+        'lowercase_static_reference' => true,
+        'magic_constant_casing' => true,
+        'magic_method_casing' => true,
+        'mb_str_functions' => false, // No, too dangerous to change that
+        'method_argument_space' => true,
         'method_chaining_indentation' => true,
-        'no_alias_functions' => false,
-        'no_superfluous_phpdoc_tags' => false,
-        'non_printable_character' => [
-            'use_escape_sequences_in_strings' => true,
-        ],
-        'phpdoc_align' => [
-            'align' => 'left',
-        ],
-        'phpdoc_summary' => false,
-        'protected_to_private' => false,
-        'self_accessor' => false,
+        'modernize_types_casting' => true,
+        'multiline_comment_opening_closing' => true,
+        'multiline_whitespace_before_semicolons' => true,
+        'native_constant_invocation' => false, // Micro optimization that look messy
+        'native_function_casing' => true,
+        'native_function_invocation' => false, // I suppose this would be best, but I am still unconvinced about the visual aspect of it
+        'native_function_type_declaration_casing' => true,
+        'new_with_braces' => true,
+        'no_alias_functions' => true,
+        'no_alternative_syntax' => true,
+        'no_binary_string' => true,
+        'no_blank_lines_after_class_opening' => true,
+        'no_blank_lines_after_phpdoc' => true,
+        'no_blank_lines_before_namespace' => false, // we want 1 blank line before namespace
+        'no_break_comment' => true,
+        'no_closing_tag' => true,
+        'no_empty_comment' => true,
+        'no_empty_phpdoc' => true,
+        'no_empty_statement' => true,
+        'no_extra_blank_lines' => true,
+        'no_homoglyph_names' => true,
+        'no_leading_import_slash' => true,
+        'no_leading_namespace_whitespace' => true,
+        'no_mixed_echo_print' => true,
+        'no_multiline_whitespace_around_double_arrow' => true,
+        'no_null_property_initialization' => true,
+        'no_php4_constructor' => true,
+        'no_short_bool_cast' => true,
+        'echo_tag_syntax' => ['format' => 'long'],
+        'no_singleline_whitespace_before_semicolons' => true,
+        'no_spaces_after_function_name' => true,
+        'no_spaces_around_offset' => true,
+        'no_spaces_inside_parenthesis' => true,
+        'no_superfluous_elseif' => false, // Might be risky on a huge code base
+        'no_superfluous_phpdoc_tags' => ['allow_mixed' => true],
+        'no_trailing_comma_in_list_call' => true,
+        'no_trailing_comma_in_singleline_array' => true,
+        'no_trailing_whitespace' => true,
+        'no_trailing_whitespace_in_comment' => true,
+        'no_unneeded_control_parentheses' => true,
+        'no_unneeded_curly_braces' => true,
+        'no_unneeded_final_method' => true,
+        'no_unreachable_default_argument_value' => true,
+        'no_unset_cast' => true,
+        'no_unset_on_property' => true,
+        'no_unused_imports' => true,
+        'no_useless_else' => true,
+        'no_useless_return' => true,
+        'no_whitespace_before_comma_in_array' => true,
+        'no_whitespace_in_blank_line' => true,
+        'non_printable_character' => true,
+        'normalize_index_brace' => true,
+        'not_operator_with_space' => false, // No we prefer to keep '!' without spaces
+        'not_operator_with_successor_space' => false, // idem
+        'nullable_type_declaration_for_default_null_value' => true,
+        'object_operator_without_whitespace' => true,
+        'ordered_class_elements' => false, // We prefer to keep some freedom
+        'ordered_imports' => true,
+        'ordered_interfaces' => true,
+        'php_unit_construct' => true,
+        'php_unit_dedicate_assert' => true,
+        'php_unit_dedicate_assert_internal_type' => true,
+        'php_unit_expectation' => true,
+        'php_unit_fqcn_annotation' => true,
+        'php_unit_internal_class' => false, // Because tests are excluded from package
+        'php_unit_method_casing' => true,
+        'php_unit_mock' => true,
+        'php_unit_mock_short_will_return' => true,
+        'php_unit_namespaced' => true,
+        'php_unit_no_expectation_annotation' => true,
+        'phpdoc_order_by_value' => ['annotations' => ['covers']],
+        'php_unit_set_up_tear_down_visibility' => true,
+        'php_unit_size_class' => false, // That seems extra work to maintain for little benefits
+        'php_unit_strict' => false, // We sometime actually need assertEquals
+        'php_unit_test_annotation' => true,
+        'php_unit_test_case_static_method_calls' => ['call_type' => 'self'],
+        'php_unit_test_class_requires_covers' => false, // We don't care as much as we should about coverage
+        'phpdoc_add_missing_param_annotation' => false, // Don't add things that bring no value
+        'phpdoc_align' => false, // Waste of time
+        'phpdoc_annotation_without_dot' => true,
+        'phpdoc_indent' => true,
+        //'phpdoc_inline_tag' => true,
+        'phpdoc_line_span' => false, // Unfortunately our old comments turn even uglier with this
+        'phpdoc_no_access' => true,
+        'phpdoc_no_alias_tag' => true,
+        'phpdoc_no_empty_return' => true,
+        'phpdoc_no_package' => true,
+        'phpdoc_no_useless_inheritdoc' => true,
+        'phpdoc_order' => true,
+        'phpdoc_return_self_reference' => true,
+        'phpdoc_scalar' => true,
+        'phpdoc_separation' => true,
+        'phpdoc_single_line_var_spacing' => true,
+        'phpdoc_summary' => true,
+        'phpdoc_to_comment' => false, // interferes with annotations
+        'phpdoc_to_param_type' => false, // Because experimental, but interesting for one shot use
+        'phpdoc_to_return_type' => false, // idem
+        'phpdoc_trim' => true,
+        'phpdoc_trim_consecutive_blank_line_separation' => true,
+        'phpdoc_types' => true,
+        'phpdoc_types_order' => true,
+        'phpdoc_var_annotation_correct_order' => true,
+        'phpdoc_var_without_name' => true,
+        'pow_to_exponentiation' => true,
+        'protected_to_private' => true,
+        'psr_autoloading' => true,
+        'random_api_migration' => true,
+        'return_assignment' => false, // Sometimes useful for clarity or debug
+        'return_type_declaration' => true,
+        'self_accessor' => true,
+        'self_static_accessor' => true,
+        'semicolon_after_instruction' => false, // Buggy in `samples/index.php`
+        'set_type_to_cast' => true,
+        'short_scalar_cast' => true,
+        'simple_to_complex_string_variable' => false, // Would differ from TypeScript without obvious advantages
+        'simplified_null_return' => false, // Even if technically correct we prefer to be explicit
+        'single_blank_line_at_eof' => true,
+        'single_blank_line_before_namespace' => true,
+        'single_class_element_per_statement' => true,
+        'single_import_per_statement' => true,
+        'single_line_after_imports' => true,
+        'single_line_comment_style' => true,
+        'single_line_throw' => false, // I don't see any reason for having a special case for Exception
+        'single_quote' => true,
+        'single_trait_insert_per_statement' => true,
+        'space_after_semicolon' => true,
+        'standardize_increment' => true,
+        'standardize_not_equals' => true,
+        'static_lambda' => false, // Risky if we can't guarantee nobody use `bindTo()`
+        'strict_comparison' => false, // No, too dangerous to change that
+        'strict_param' => false, // No, too dangerous to change that
+        'string_line_ending' => true,
+        'switch_case_semicolon_to_colon' => true,
+        'switch_case_space' => true,
+        'ternary_operator_spaces' => true,
+        'ternary_to_null_coalescing' => true,
+        'trailing_comma_in_multiline' => true,
+        'trim_array_spaces' => true,
+        'unary_operator_spaces' => true,
+        'visibility_required' => ['elements' => ['property', 'method']], // not const
+        'void_return' => true,
+        'whitespace_after_comma_in_array' => true,
         'yoda_style' => false,
-        'single_line_throw' => false,
-        'no_alias_language_construct_call' => false,
     ])
     ->getFinder()
     ->in(__DIR__)
diff --git a/docs/changes/1.1.0.md b/docs/changes/1.1.0.md
index 47613d194d..f92efb5674 100644
--- a/docs/changes/1.1.0.md
+++ b/docs/changes/1.1.0.md
@@ -1,11 +1,15 @@
-# 1.0.0 - WIP
+# 1.1.0 - WIP
 
 ## Features
 
-- Support for axis options - [@mindline](https://github.com/mindline-analytics) GH-676
+- Support for axis options - [@mindline](https://github.com/mindline-analytics) in [#676](https://github.com/PHPOffice/PHPPresentatio /pull/676)
     - Axis intersection point (axis crossing) through `setCrossesAt`/ `getCrossesAt`
     - Reverse axis order through `setIsReversedOrder`/ `isReversedOrder`
     - PowerPoint2007 Writer
-- Support for Hyperlink Text Color - [@MartynasJanu](https://github.com/MartynasJanu) & [@Progi1984](https://github.com/Progi1984) GH-682
+- Support for Hyperlink Text Color - [@MartynasJanu](https://github.com/MartynasJanu) & [@Progi1984](https://github.com/Progi1984) in [#682](https://github.com/PHPOffice/PHPPresentatio /pull/682)
     - PowerPoint2007 Reader
     - PowerPoint2007 Writer
+
+## Bugfixes
+
+- Fixed CI - [@Progi1984](https://github.com/Progi1984) in [#766](https://github.com/PHPOffice/PHPPresentatio /pull/766)
\ No newline at end of file
diff --git a/samples/Sample_03_Image.php b/samples/Sample_03_Image.php
index 8c6e0e847c..00159e5259 100644
--- a/samples/Sample_03_Image.php
+++ b/samples/Sample_03_Image.php
@@ -17,7 +17,7 @@
 
 // Generate an image
 echo date('H:i:s') . ' Generate an image' . EOL;
-$gdImage = @imagecreatetruecolor(140, 20) or exit('Cannot Initialize new GD image stream');
+$gdImage = @imagecreatetruecolor(140, 20) || exit('Cannot Initialize new GD image stream');
 $textColor = imagecolorallocate($gdImage, 255, 255, 255);
 imagestring($gdImage, 1, 5, 5, 'Created with PHPPresentation', $textColor);
 
diff --git a/samples/Sample_05_Chart.php b/samples/Sample_05_Chart.php
index 9169b1f43b..201d9a46a4 100644
--- a/samples/Sample_05_Chart.php
+++ b/samples/Sample_05_Chart.php
@@ -21,7 +21,7 @@
 use PhpOffice\PhpPresentation\Style\Fill;
 use PhpOffice\PhpPresentation\Style\Shadow;
 
-function fnSlide_Area(PhpPresentation $objPHPPresentation)
+function fnSlide_Area(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -71,7 +71,7 @@ function fnSlide_Area(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_Bar(PhpPresentation $objPHPPresentation)
+function fnSlide_Bar(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -125,7 +125,7 @@ function fnSlide_Bar(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_BarHorizontal(PhpPresentation $objPHPPresentation)
+function fnSlide_BarHorizontal(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -161,7 +161,7 @@ function fnSlide_BarHorizontal(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_BarStacked(PhpPresentation $objPHPPresentation)
+function fnSlide_BarStacked(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -223,7 +223,7 @@ function fnSlide_BarStacked(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_BarPercentStacked(PhpPresentation $objPHPPresentation)
+function fnSlide_BarPercentStacked(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -302,7 +302,7 @@ function fnSlide_BarPercentStacked(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_Bar3D(PhpPresentation $objPHPPresentation)
+function fnSlide_Bar3D(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -356,7 +356,7 @@ function fnSlide_Bar3D(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_Bar3DHorizontal(PhpPresentation $objPHPPresentation)
+function fnSlide_Bar3DHorizontal(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -395,7 +395,7 @@ function fnSlide_Bar3DHorizontal(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_Doughnut(PhpPresentation $objPHPPresentation)
+function fnSlide_Doughnut(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -450,7 +450,7 @@ function fnSlide_Doughnut(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->setPosition(Legend::POSITION_LEFT);
 }
 
-function fnSlide_Pie3D(PhpPresentation $objPHPPresentation)
+function fnSlide_Pie3D(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -499,7 +499,7 @@ function fnSlide_Pie3D(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_Pie(PhpPresentation $objPHPPresentation)
+function fnSlide_Pie(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -550,7 +550,7 @@ function fnSlide_Pie(PhpPresentation $objPHPPresentation)
     $shape->getLegend()->getFont()->setItalic(true);
 }
 
-function fnSlide_Radar(PhpPresentation $objPHPPresentation)
+function fnSlide_Radar(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
@@ -607,7 +607,7 @@ function fnSlide_Radar(PhpPresentation $objPHPPresentation)
         ->setStartColor(new Color(Color::COLOR_BLUE)); // 0000FF
 }
 
-function fnSlide_Scatter(PhpPresentation $objPHPPresentation)
+function fnSlide_Scatter(PhpPresentation $objPHPPresentation): void
 {
     global $oFill;
     global $oShadow;
diff --git a/samples/Sample_06_Fill.php b/samples/Sample_06_Fill.php
index e917a34f90..41bc149a61 100644
--- a/samples/Sample_06_Fill.php
+++ b/samples/Sample_06_Fill.php
@@ -46,15 +46,19 @@
     switch ($inc) {
         case 1:
             $shape->getFill()->setFillType(Fill::FILL_NONE);
+
             break;
         case 2:
             $shape->getFill()->setFillType(Fill::FILL_GRADIENT_LINEAR)->setRotation(90)->setStartColor(new Color('FF4672A8'))->setEndColor(new Color('FF000000'));
+
             break;
         case 3:
             $shape->getFill()->setFillType(Fill::FILL_GRADIENT_PATH)->setRotation(90)->setStartColor(new Color('FF4672A8'))->setEndColor(new Color('FF000000'));
+
             break;
         case 4:
             $shape->getFill()->setFillType(Fill::FILL_SOLID)->setRotation(90)->setStartColor(new Color('FF4672A8'))->setEndColor(new Color('FF4672A8'));
+
             break;
     }
 
diff --git a/samples/Sample_07_Border.php b/samples/Sample_07_Border.php
index 24816fedda..fff1aa1bb2 100644
--- a/samples/Sample_07_Border.php
+++ b/samples/Sample_07_Border.php
@@ -38,15 +38,19 @@
     switch ($inc) {
         case 1:
             $shape->getBorder()->setColor(new Color('FF4672A8'))->setDashStyle(Border::DASH_SOLID)->setLineStyle(Border::LINE_DOUBLE);
+
             break;
         case 2:
             $shape->getBorder()->setColor(new Color('FF4672A8'))->setDashStyle(Border::DASH_DASH)->setLineStyle(Border::LINE_SINGLE);
+
             break;
         case 3:
             $shape->getBorder()->setColor(new Color('FF4672A8'))->setDashStyle(Border::DASH_DOT)->setLineStyle(Border::LINE_THICKTHIN);
+
             break;
         case 4:
             $shape->getBorder()->setColor(new Color('FF4672A8'))->setDashStyle(Border::DASH_LARGEDASHDOT)->setLineStyle(Border::LINE_THINTHICK);
+
             break;
     }
 
diff --git a/samples/Sample_11_Shape.php b/samples/Sample_11_Shape.php
index 37dc5a221d..af3059f2b4 100644
--- a/samples/Sample_11_Shape.php
+++ b/samples/Sample_11_Shape.php
@@ -7,7 +7,7 @@
 
 include_once 'Sample_Header.php';
 
-function fnSlideRichText(PhpPresentation $objPHPPresentation)
+function fnSlideRichText(PhpPresentation $objPHPPresentation): void
 {
     // Create templated slide
     echo date('H:i:s') . ' Create templated slide' . EOL;
@@ -35,7 +35,7 @@ function fnSlideRichText(PhpPresentation $objPHPPresentation)
     $textRun->getFont()->setColor(new Color('FF000000'));
 }
 
-function fnSlideRichTextLineSpacing(PhpPresentation $objPHPPresentation)
+function fnSlideRichTextLineSpacing(PhpPresentation $objPHPPresentation): void
 {
     // Create templated slide
     echo date('H:i:s') . ' Create templated slide' . EOL;
@@ -81,7 +81,7 @@ function fnSlideRichTextLineSpacing(PhpPresentation $objPHPPresentation)
     $shape->createTextRun('Line Spacing 300');
 }
 
-function fnSlideRichTextShadow(PhpPresentation $objPHPPresentation)
+function fnSlideRichTextShadow(PhpPresentation $objPHPPresentation): void
 {
     // Create templated slide
     echo date('H:i:s') . ' Create templated slide' . EOL;
@@ -101,7 +101,7 @@ function fnSlideRichTextShadow(PhpPresentation $objPHPPresentation)
     $textRun->getFont()->setColor(new Color('FF000000'));
 }
 
-function fnSlideRichTextList(PhpPresentation $objPHPPresentation)
+function fnSlideRichTextList(PhpPresentation $objPHPPresentation): void
 {
     // Create templated slide
     echo date('H:i:s') . ' Create templated slide' . EOL;
diff --git a/samples/Sample_15_Background.php b/samples/Sample_15_Background.php
index 74135eeceb..9e1280fd99 100644
--- a/samples/Sample_15_Background.php
+++ b/samples/Sample_15_Background.php
@@ -29,9 +29,7 @@
 $oSlide2->addShape(clone $oShapeRichText);
 
 // Slide > Background > Image
-/*
- * @link : http://publicdomainarchive.com/public-domain-images-cave-red-rocks-light-beam-cavern/
- */
+// @link : http://publicdomainarchive.com/public-domain-images-cave-red-rocks-light-beam-cavern/
 $oBkgImage = new Image();
 $oBkgImage->setPath(__DIR__ . '/resources/background.jpg');
 $oSlide2->setBackground($oBkgImage);
diff --git a/samples/Sample_Header.php b/samples/Sample_Header.php
index eb16a62a3c..3f9e7cc413 100644
--- a/samples/Sample_Header.php
+++ b/samples/Sample_Header.php
@@ -1,7 +1,7 @@
 <?php
 /**
  * Header file.
-*/
+ */
 use PhpOffice\PhpPresentation\AbstractShape;
 use PhpOffice\PhpPresentation\Autoloader;
 use PhpOffice\PhpPresentation\DocumentLayout;
@@ -117,7 +117,7 @@ function write($phpPresentation, $filename, $writers)
     // Write documents
     foreach ($writers as $writer => $extension) {
         $result .= date('H:i:s') . " Write to {$writer} format";
-        if (!is_null($extension)) {
+        if (null !== $extension) {
             $xmlWriter = IOFactory::createWriter($phpPresentation, $writer);
             $xmlWriter->save(__DIR__ . "/{$filename}.{$extension}");
             rename(__DIR__ . "/{$filename}.{$extension}", __DIR__ . "/results/{$filename}.{$extension}");
@@ -158,7 +158,7 @@ function getEndingNotes($writers)
             $result .= '<p>&nbsp;</p>';
             $result .= '<p>Results: ';
             foreach ($types as $type) {
-                if (!is_null($type)) {
+                if (null !== $type) {
                     $resultFile = 'results/' . SCRIPT_FILENAME . '.' . $type;
                     if (file_exists($resultFile)) {
                         $result .= "<a href='{$resultFile}' class='btn btn-primary'>{$type}</a> ";
@@ -200,9 +200,10 @@ function createTemplatedSlide(PhpOffice\PhpPresentation\PhpPresentation $objPHPP
     return $slide;
 }
 
-class PhpPptTree
+class Sample_Header
 {
     protected $oPhpPresentation;
+
     protected $htmlOutput;
 
     public function __construct(PhpPresentation $oPHPPpt)
@@ -230,12 +231,12 @@ public function display()
         return $this->htmlOutput;
     }
 
-    protected function append($sHTML)
+    protected function append($sHTML): void
     {
         $this->htmlOutput .= $sHTML;
     }
 
-    protected function displayPhpPresentation(PhpPresentation $oPHPPpt)
+    protected function displayPhpPresentation(PhpPresentation $oPHPPpt): void
     {
         $this->append('<li><span><i class="fa fa-folder-open"></i> PhpPresentation</span>');
         $this->append('<ul>');
@@ -265,7 +266,7 @@ protected function displayPhpPresentation(PhpPresentation $oPHPPpt)
         $this->append('</li>');
     }
 
-    protected function displayShape(AbstractShape $shape)
+    protected function displayShape(AbstractShape $shape): void
     {
         if ($shape instanceof Drawing\Gd) {
             $this->append('<li><span class="shape" id="div' . $shape->getHashCode() . '">Shape "Drawing\Gd"</span></li>');
@@ -282,7 +283,7 @@ protected function displayShape(AbstractShape $shape)
         }
     }
 
-    protected function displayPhpPresentationInfo(PhpPresentation $oPHPPpt)
+    protected function displayPhpPresentationInfo(PhpPresentation $oPHPPpt): void
     {
         $this->append('<div class="infoBlk" id="divPhpPresentationInfo">');
         $this->append('<dl>');
@@ -348,7 +349,7 @@ protected function displayPhpPresentationInfo(PhpPresentation $oPHPPpt)
         }
     }
 
-    protected function displayShapeInfo(AbstractShape $oShape)
+    protected function displayShapeInfo(AbstractShape $oShape): void
     {
         $this->append('<div class="infoBlk" id="div' . $oShape->getHashCode() . 'Info">');
         $this->append('<dl>');
@@ -360,18 +361,20 @@ protected function displayShapeInfo(AbstractShape $oShape)
         $this->append('<dt>Rotation</dt><dd>' . $oShape->getRotation() . '°</dd>');
         $this->append('<dt>Hyperlink</dt><dd>' . ucfirst(var_export($oShape->hasHyperlink(), true)) . '</dd>');
         $this->append('<dt>Fill</dt>');
-        if (is_null($oShape->getFill())) {
+        if (null === $oShape->getFill()) {
             $this->append('<dd>None</dd>');
         } else {
             switch ($oShape->getFill()->getFillType()) {
                 case \PhpOffice\PhpPresentation\Style\Fill::FILL_NONE:
                     $this->append('<dd>None</dd>');
+
                     break;
                 case \PhpOffice\PhpPresentation\Style\Fill::FILL_SOLID:
                     $this->append('<dd>Solid (');
                     $this->append('Color : #' . $oShape->getFill()->getStartColor()->getRGB());
                     $this->append(' - Alpha : ' . $oShape->getFill()->getStartColor()->getAlpha() . '%');
                     $this->append(')</dd>');
+
                     break;
             }
         }
@@ -454,9 +457,9 @@ protected function displayShapeInfo(AbstractShape $oShape)
                 $this->append('</dl></dd></dl>');
             }
             $this->append('</dd>');
-        } else {
-            // Add another shape
         }
+        // Add another shape
+
         $this->append('</dl>');
         $this->append('</div>');
     }
@@ -471,6 +474,7 @@ protected function getConstantName($class, $search, $startWith = '')
                 if (empty($startWith) || (!empty($startWith) && 0 === strpos($key, $startWith))) {
                     $constName = $key;
                 }
+
                 break;
             }
         }
diff --git a/samples/index.php b/samples/index.php
index c45af5f7f8..efda7ee8ef 100644
--- a/samples/index.php
+++ b/samples/index.php
@@ -1,7 +1,7 @@
 <?php
 include_once 'Sample_Header.php';
 $requirements = [
-    'php' => ['PHP 5.3.0', version_compare(phpversion(), '5.3.0', '>=')],
+    'php' => ['PHP 5.3.0', version_compare(PHP_VERSION, '5.3.0', '>=')],
     'xml' => ['PHP extension XML', extension_loaded('xml')],
     'zip' => ['PHP extension ZipArchive (optional)', extension_loaded('zip')],
     'gd' => ['PHP extension GD (optional)', extension_loaded('gd')],
@@ -24,7 +24,7 @@
     echo '<h3>Requirement check:</h3>';
     echo '<ul>';
     foreach ($requirements as $key => $value) {
-        list($label, $result) = $value;
+        [$label, $result] = $value;
         $status = $result ? 'passed' : 'failed';
         echo "<li>{$label} ... <span class='{$status}'>{$status}</span></li>";
     }
@@ -33,7 +33,7 @@
 } else {
     echo 'Requirement check:' . PHP_EOL;
     foreach ($requirements as $key => $value) {
-        list($label, $result) = $value;
+        [$label, $result] = $value;
         $status = $result ? '32m passed' : '31m failed';
         echo "{$label} ... \033[{$status}\033[0m" . PHP_EOL;
     }
diff --git a/src/PhpPresentation/AbstractShape.php b/src/PhpPresentation/AbstractShape.php
index c8d3df00d8..a7bdcac9e5 100644
--- a/src/PhpPresentation/AbstractShape.php
+++ b/src/PhpPresentation/AbstractShape.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,7 +34,7 @@ abstract class AbstractShape implements ComparableInterface
     /**
      * Container.
      *
-     * @var ShapeContainerInterface|null
+     * @var null|ShapeContainerInterface
      */
     protected $container;
 
@@ -68,7 +67,7 @@ abstract class AbstractShape implements ComparableInterface
     protected $height;
 
     /**
-     * @var Fill|null
+     * @var null|Fill
      */
     private $fill;
 
@@ -89,17 +88,17 @@ abstract class AbstractShape implements ComparableInterface
     /**
      * Shadow.
      *
-     * @var Shadow|null
+     * @var null|Shadow
      */
     protected $shadow;
 
     /**
-     * @var Hyperlink|null
+     * @var null|Hyperlink
      */
     protected $hyperlink;
 
     /**
-     * @var Placeholder|null
+     * @var null|Placeholder
      */
     protected $placeholder;
 
@@ -147,16 +146,14 @@ public function getContainer(): ?ShapeContainerInterface
      * @param ShapeContainerInterface $pValue
      * @param bool $pOverrideOld If a Slide has already been assigned, overwrite it and remove image from old Slide?
      *
-     * @throws ShapeContainerAlreadyAssignedException
-     *
      * @return $this
      */
-    public function setContainer(ShapeContainerInterface $pValue = null, $pOverrideOld = false)
+    public function setContainer(?ShapeContainerInterface $pValue = null, $pOverrideOld = false)
     {
-        if (is_null($this->container)) {
+        if (null === $this->container) {
             // Add drawing to ShapeContainerInterface
             $this->container = $pValue;
-            if (!is_null($this->container)) {
+            if (null !== $this->container) {
                 $this->container->getShapeCollection()->append($this);
             }
         } else {
@@ -168,6 +165,7 @@ public function setContainer(ShapeContainerInterface $pValue = null, $pOverrideO
                     if ($iterator->current()->getHashCode() == $this->getHashCode()) {
                         $this->container->getShapeCollection()->offsetUnset($iterator->key());
                         $this->container = null;
+
                         break;
                     }
                     $iterator->next();
@@ -311,7 +309,7 @@ public function getFill(): ?Fill
         return $this->fill;
     }
 
-    public function setFill(Fill $pValue = null): self
+    public function setFill(?Fill $pValue = null): self
     {
         $this->fill = $pValue;
 
@@ -331,7 +329,7 @@ public function getShadow(): ?Shadow
     /**
      * @return $this
      */
-    public function setShadow(Shadow $pValue = null)
+    public function setShadow(?Shadow $pValue = null)
     {
         $this->shadow = $pValue;
 
@@ -345,15 +343,15 @@ public function setShadow(Shadow $pValue = null)
      */
     public function hasHyperlink()
     {
-        return !is_null($this->hyperlink);
+        return null !== $this->hyperlink;
     }
 
     /**
-     * Get Hyperlink
+     * Get Hyperlink.
      */
     public function getHyperlink(): Hyperlink
     {
-        if (is_null($this->hyperlink)) {
+        if (null === $this->hyperlink) {
             $this->hyperlink = new Hyperlink();
         }
 
@@ -361,9 +359,9 @@ public function getHyperlink(): Hyperlink
     }
 
     /**
-     * Set Hyperlink
+     * Set Hyperlink.
      */
-    public function setHyperlink(Hyperlink $pHyperlink = null): self
+    public function setHyperlink(?Hyperlink $pHyperlink = null): self
     {
         $this->hyperlink = $pHyperlink;
 
@@ -377,7 +375,7 @@ public function setHyperlink(Hyperlink $pHyperlink = null): self
      */
     public function getHashCode(): string
     {
-        return md5((is_object($this->container) ? $this->container->getHashCode() : '') . $this->offsetX . $this->offsetY . $this->width . $this->height . $this->rotation . (is_null($this->getFill()) ? '' : $this->getFill()->getHashCode()) . (is_null($this->shadow) ? '' : $this->shadow->getHashCode()) . (is_null($this->hyperlink) ? '' : $this->hyperlink->getHashCode()) . __CLASS__);
+        return md5((is_object($this->container) ? $this->container->getHashCode() : '') . $this->offsetX . $this->offsetY . $this->width . $this->height . $this->rotation . (null === $this->getFill() ? '' : $this->getFill()->getHashCode()) . (null === $this->shadow ? '' : $this->shadow->getHashCode()) . (null === $this->hyperlink ? '' : $this->hyperlink->getHashCode()) . __CLASS__);
     }
 
     /**
@@ -386,7 +384,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
@@ -412,7 +410,7 @@ public function setHashIndex(int $value)
 
     public function isPlaceholder(): bool
     {
-        return !is_null($this->placeholder);
+        return null !== $this->placeholder;
     }
 
     public function getPlaceholder(): ?Placeholder
diff --git a/src/PhpPresentation/Autoloader.php b/src/PhpPresentation/Autoloader.php
index 6c7211fde6..693b43aeeb 100644
--- a/src/PhpPresentation/Autoloader.php
+++ b/src/PhpPresentation/Autoloader.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/ComparableInterface.php b/src/PhpPresentation/ComparableInterface.php
index 7fefbda1c0..ed958b17ea 100644
--- a/src/PhpPresentation/ComparableInterface.php
+++ b/src/PhpPresentation/ComparableInterface.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -38,7 +37,7 @@ public function getHashCode(): string;
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int;
 
diff --git a/src/PhpPresentation/DocumentLayout.php b/src/PhpPresentation/DocumentLayout.php
index bf79104070..ec1a40c61d 100644
--- a/src/PhpPresentation/DocumentLayout.php
+++ b/src/PhpPresentation/DocumentLayout.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -131,12 +130,14 @@ public function setDocumentLayout($pValue = self::LAYOUT_SCREEN_4X3, $isLandscap
                 $this->layout = $pValue;
                 $this->dimensionX = $this->dimension[$this->layout]['cx'];
                 $this->dimensionY = $this->dimension[$this->layout]['cy'];
+
                 break;
             case self::LAYOUT_CUSTOM:
             default:
                 $this->layout = self::LAYOUT_CUSTOM;
                 $this->dimensionX = $pValue['cx'];
                 $this->dimensionY = $pValue['cy'];
+
                 break;
         }
 
@@ -196,18 +197,23 @@ protected function convertUnit(float $value, string $fromUnit, string $toUnit):
         switch ($fromUnit) {
             case self::UNIT_MILLIMETER:
                 $value *= 36000;
+
                 break;
             case self::UNIT_CENTIMETER:
                 $value *= 360000;
+
                 break;
             case self::UNIT_INCH:
                 $value *= 914400;
+
                 break;
             case self::UNIT_PIXEL:
                 $value = Drawing::pixelsToEmu($value);
+
                 break;
             case self::UNIT_POINT:
                 $value *= 12700;
+
                 break;
             case self::UNIT_EMU:
             default:
@@ -218,18 +224,23 @@ protected function convertUnit(float $value, string $fromUnit, string $toUnit):
         switch ($toUnit) {
             case self::UNIT_MILLIMETER:
                 $value /= 36000;
+
                 break;
             case self::UNIT_CENTIMETER:
                 $value /= 360000;
+
                 break;
             case self::UNIT_INCH:
                 $value /= 914400;
+
                 break;
             case self::UNIT_PIXEL:
                 $value = Drawing::emuToPixels((int) $value);
+
                 break;
             case self::UNIT_POINT:
                 $value /= 12700;
+
                 break;
             case self::UNIT_EMU:
             default:
diff --git a/src/PhpPresentation/DocumentProperties.php b/src/PhpPresentation/DocumentProperties.php
index ab45420437..7c48cef1d4 100644
--- a/src/PhpPresentation/DocumentProperties.php
+++ b/src/PhpPresentation/DocumentProperties.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -110,7 +109,7 @@ class DocumentProperties
     private $customProperties = [];
 
     /**
-     * Create a new \PhpOffice\PhpPresentation\DocumentProperties
+     * Create a new \PhpOffice\PhpPresentation\DocumentProperties.
      */
     public function __construct()
     {
@@ -194,7 +193,7 @@ public function getCreated()
      */
     public function setCreated($pValue = null)
     {
-        if (is_null($pValue)) {
+        if (null === $pValue) {
             $pValue = time();
         }
         $this->created = $pValue;
@@ -221,7 +220,7 @@ public function getModified()
      */
     public function setModified($pValue = null)
     {
-        if (is_null($pValue)) {
+        if (null === $pValue) {
             $pValue = time();
         }
         $this->modified = $pValue;
@@ -385,10 +384,6 @@ public function getCustomProperties(): array
 
     /**
      * Check if a Custom Property is defined.
-     *
-     * @param string $propertyName
-     *
-     * @return bool
      */
     public function isCustomPropertySet(string $propertyName): bool
     {
@@ -398,9 +393,7 @@ public function isCustomPropertySet(string $propertyName): bool
     /**
      * Get a Custom Property Value.
      *
-     * @param string $propertyName
-     *
-     * @return mixed|null
+     * @return null|mixed
      */
     public function getCustomPropertyValue(string $propertyName)
     {
@@ -413,10 +406,6 @@ public function getCustomPropertyValue(string $propertyName)
 
     /**
      * Get a Custom Property Type.
-     *
-     * @param string $propertyName
-     *
-     * @return string|null
      */
     public function getCustomPropertyType(string $propertyName): ?string
     {
@@ -430,16 +419,13 @@ public function getCustomPropertyType(string $propertyName): ?string
     /**
      * Set a Custom Property.
      *
-     * @param string $propertyName
      * @param mixed $propertyValue
-     * @param string|null $propertyType
+     * @param null|string $propertyType
      *                                  'i' : Integer
      *                                  'f' : Floating Point
      *                                  's' : String
      *                                  'd' : Date/Time
      *                                  'b' : Boolean
-     *
-     * @return self
      */
     public function setCustomProperty(string $propertyName, $propertyValue = '', ?string $propertyType = null): self
     {
diff --git a/src/PhpPresentation/Exception/DirectoryNotFoundException.php b/src/PhpPresentation/Exception/DirectoryNotFoundException.php
index bfd444c440..e1c64e38be 100644
--- a/src/PhpPresentation/Exception/DirectoryNotFoundException.php
+++ b/src/PhpPresentation/Exception/DirectoryNotFoundException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/FeatureNotImplementedException.php b/src/PhpPresentation/Exception/FeatureNotImplementedException.php
index 56160e6bbe..2ba4a04ed3 100644
--- a/src/PhpPresentation/Exception/FeatureNotImplementedException.php
+++ b/src/PhpPresentation/Exception/FeatureNotImplementedException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/FileCopyException.php b/src/PhpPresentation/Exception/FileCopyException.php
index a6574bce5d..84dd930881 100644
--- a/src/PhpPresentation/Exception/FileCopyException.php
+++ b/src/PhpPresentation/Exception/FileCopyException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/FileNotFoundException.php b/src/PhpPresentation/Exception/FileNotFoundException.php
index 368a32b97f..bf825a4461 100644
--- a/src/PhpPresentation/Exception/FileNotFoundException.php
+++ b/src/PhpPresentation/Exception/FileNotFoundException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/FileRemoveException.php b/src/PhpPresentation/Exception/FileRemoveException.php
index e9b4e306af..04bd141ac1 100644
--- a/src/PhpPresentation/Exception/FileRemoveException.php
+++ b/src/PhpPresentation/Exception/FileRemoveException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/InvalidClassException.php b/src/PhpPresentation/Exception/InvalidClassException.php
index 06642d5ff3..e8813fbb49 100644
--- a/src/PhpPresentation/Exception/InvalidClassException.php
+++ b/src/PhpPresentation/Exception/InvalidClassException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/InvalidFileFormatException.php b/src/PhpPresentation/Exception/InvalidFileFormatException.php
index 4dcbff7b82..1894d4e1e1 100644
--- a/src/PhpPresentation/Exception/InvalidFileFormatException.php
+++ b/src/PhpPresentation/Exception/InvalidFileFormatException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/InvalidParameterException.php b/src/PhpPresentation/Exception/InvalidParameterException.php
index a6a97cf97a..9618096238 100644
--- a/src/PhpPresentation/Exception/InvalidParameterException.php
+++ b/src/PhpPresentation/Exception/InvalidParameterException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/OutOfBoundsException.php b/src/PhpPresentation/Exception/OutOfBoundsException.php
index 7946c60752..38789d720e 100644
--- a/src/PhpPresentation/Exception/OutOfBoundsException.php
+++ b/src/PhpPresentation/Exception/OutOfBoundsException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/PhpPresentationException.php b/src/PhpPresentation/Exception/PhpPresentationException.php
index 52392894a1..629b70a0aa 100644
--- a/src/PhpPresentation/Exception/PhpPresentationException.php
+++ b/src/PhpPresentation/Exception/PhpPresentationException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/ShapeContainerAlreadyAssignedException.php b/src/PhpPresentation/Exception/ShapeContainerAlreadyAssignedException.php
index cd39cb0477..c210830110 100644
--- a/src/PhpPresentation/Exception/ShapeContainerAlreadyAssignedException.php
+++ b/src/PhpPresentation/Exception/ShapeContainerAlreadyAssignedException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Exception/UnauthorizedMimetypeException.php b/src/PhpPresentation/Exception/UnauthorizedMimetypeException.php
index 01a8b5b66d..67f03fc190 100644
--- a/src/PhpPresentation/Exception/UnauthorizedMimetypeException.php
+++ b/src/PhpPresentation/Exception/UnauthorizedMimetypeException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -23,7 +22,6 @@
 class UnauthorizedMimetypeException extends PhpPresentationException
 {
     /**
-     * @param string $expectedMimetype
      * @param array<string> $authorizedMimetypes
      */
     public function __construct(string $expectedMimetype, array $authorizedMimetypes)
diff --git a/src/PhpPresentation/Exception/UndefinedChartTypeException.php b/src/PhpPresentation/Exception/UndefinedChartTypeException.php
index 5e77181a0c..6b53f26f78 100644
--- a/src/PhpPresentation/Exception/UndefinedChartTypeException.php
+++ b/src/PhpPresentation/Exception/UndefinedChartTypeException.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/GeometryCalculator.php b/src/PhpPresentation/GeometryCalculator.php
index 7eccbf8959..2c050929ed 100644
--- a/src/PhpPresentation/GeometryCalculator.php
+++ b/src/PhpPresentation/GeometryCalculator.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/HashTable.php b/src/PhpPresentation/HashTable.php
index df5e5a29a8..6a72f5c30f 100644
--- a/src/PhpPresentation/HashTable.php
+++ b/src/PhpPresentation/HashTable.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/IOFactory.php b/src/PhpPresentation/IOFactory.php
index 0d7f90b291..88f7d4bc14 100644
--- a/src/PhpPresentation/IOFactory.php
+++ b/src/PhpPresentation/IOFactory.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -40,9 +39,6 @@ class IOFactory
 
     /**
      * Create writer.
-     *
-     * @param PhpPresentation $phpPresentation
-     * @param string $name
      */
     public static function createWriter(PhpPresentation $phpPresentation, string $name = 'PowerPoint2007'): WriterInterface
     {
@@ -51,8 +47,6 @@ public static function createWriter(PhpPresentation $phpPresentation, string $na
 
     /**
      * Create reader.
-     *
-     * @param string $name
      */
     public static function createReader(string $name): ReaderInterface
     {
@@ -61,8 +55,6 @@ public static function createReader(string $name): ReaderInterface
 
     /**
      * Loads PhpPresentation from file using automatic ReaderInterface resolution.
-     *
-     * @throws InvalidFileFormatException
      */
     public static function load(string $pFilename): PhpPresentation
     {
@@ -76,23 +68,17 @@ public static function load(string $pFilename): PhpPresentation
 
         throw new InvalidFileFormatException(
             $pFilename,
-            IOFactory::class,
+            self::class,
             'Could not automatically determine the good ' . ReaderInterface::class
         );
     }
 
     /**
-     * Load class
-     *
-     * @param string $class
-     * @param string $type
-     * @param PhpPresentation|null $phpPresentation
+     * Load class.
      *
      * @return object
-     *
-     * @throws InvalidClassException
      */
-    private static function loadClass(string $class, string $type, PhpPresentation $phpPresentation = null)
+    private static function loadClass(string $class, string $type, ?PhpPresentation $phpPresentation = null)
     {
         if (!class_exists($class)) {
             throw new InvalidClassException($class, $type . ': The class doesn\'t exist');
@@ -100,7 +86,7 @@ private static function loadClass(string $class, string $type, PhpPresentation $
         if (!self::isConcreteClass($class)) {
             throw new InvalidClassException($class, $type . ': The class is an abstract class or an interface');
         }
-        if (is_null($phpPresentation)) {
+        if (null === $phpPresentation) {
             return new $class();
         }
 
diff --git a/src/PhpPresentation/PhpPresentation.php b/src/PhpPresentation/PhpPresentation.php
index e2db811f5a..c55008348b 100644
--- a/src/PhpPresentation/PhpPresentation.php
+++ b/src/PhpPresentation/PhpPresentation.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -179,8 +178,6 @@ public function addSlide(Slide $slide): Slide
      * Remove slide by index.
      *
      * @param int $index Slide index
-     *
-     * @throws OutOfBoundsException
      */
     public function removeSlideByIndex(int $index = 0): self
     {
@@ -196,8 +193,6 @@ public function removeSlideByIndex(int $index = 0): self
      * Get slide by index.
      *
      * @param int $index Slide index
-     *
-     * @throws OutOfBoundsException
      */
     public function getSlide(int $index = 0): Slide
     {
@@ -257,8 +252,6 @@ public function getActiveSlideIndex(): int
      * Set active slide index.
      *
      * @param int $index Active slide index
-     *
-     * @throws OutOfBoundsException
      */
     public function setActiveSlideIndex(int $index = 0): Slide
     {
@@ -316,7 +309,7 @@ public function addMasterSlide(SlideMaster $slide): SlideMaster
     /**
      * Copy presentation (!= clone!).
      */
-    public function copy(): PhpPresentation
+    public function copy(): self
     {
         $copied = clone $this;
 
diff --git a/src/PhpPresentation/PresentationProperties.php b/src/PhpPresentation/PresentationProperties.php
index a8ee8eff3f..c10c915f80 100644
--- a/src/PhpPresentation/PresentationProperties.php
+++ b/src/PhpPresentation/PresentationProperties.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -71,7 +70,7 @@ class PresentationProperties
     protected $markAsFinal = false;
 
     /**
-     * @var string|null
+     * @var null|string
      */
     protected $thumbnail;
 
@@ -111,8 +110,6 @@ public function setLoopContinuouslyUntilEsc(bool $value = false): self
 
     /**
      * Return the thumbnail file path.
-     *
-     * @return string|null
      */
     public function getThumbnailPath(): ?string
     {
@@ -121,10 +118,6 @@ public function getThumbnailPath(): ?string
 
     /**
      * Define the path for the thumbnail file / preview picture.
-     *
-     * @param string $path
-     *
-     * @return self
      */
     public function setThumbnailPath(string $path = ''): self
     {
@@ -147,8 +140,6 @@ public function markAsFinal(bool $state = true): self
 
     /**
      * Return if this document is marked as final.
-     *
-     * @return bool
      */
     public function isMarkedAsFinal(): bool
     {
@@ -173,11 +164,6 @@ public function getZoom(): float
         return $this->zoom;
     }
 
-    /**
-     * @param string $value
-     *
-     * @return self
-     */
     public function setLastView(string $value = self::VIEW_SLIDE): self
     {
         if (in_array($value, $this->arrayView)) {
@@ -187,9 +173,6 @@ public function setLastView(string $value = self::VIEW_SLIDE): self
         return $this;
     }
 
-    /**
-     * @return string
-     */
     public function getLastView(): string
     {
         return $this->lastView;
@@ -207,19 +190,11 @@ public function isCommentVisible(): bool
         return $this->isCommentVisible;
     }
 
-    /**
-     * @return string
-     */
     public function getSlideshowType(): string
     {
         return $this->slideshowType;
     }
 
-    /**
-     * @param string $value
-     *
-     * @return self
-     */
     public function setSlideshowType(string $value = self::SLIDESHOW_TYPE_PRESENT): self
     {
         if (in_array($value, $this->arraySlideshowTypes)) {
diff --git a/src/PhpPresentation/Reader/ODPresentation.php b/src/PhpPresentation/Reader/ODPresentation.php
index d4fd67c05b..b9746e6c4f 100644
--- a/src/PhpPresentation/Reader/ODPresentation.php
+++ b/src/PhpPresentation/Reader/ODPresentation.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -53,24 +52,29 @@ class ODPresentation implements ReaderInterface
      * @var PhpPresentation
      */
     protected $oPhpPresentation;
+
     /**
      * Output Object.
      *
-     * @var \ZipArchive
+     * @var ZipArchive
      */
     protected $oZip;
+
     /**
      * @var array<string, array{alignment: Alignment|null, background: null, shadow: Shadow|null, fill: Fill|null, spacingAfter: int|null, spacingBefore: int|null, lineSpacingMode: null, lineSpacing: null, font: null, listStyle: null}>
      */
     protected $arrayStyles = [];
+
     /**
-     * @var array<string, array<string, string|null>>
+     * @var array<string, array<string, null|string>>
      */
     protected $arrayCommonStyles = [];
+
     /**
      * @var \PhpOffice\Common\XMLReader
      */
     protected $oXMLReader;
+
     /**
      * @var int
      */
@@ -86,8 +90,6 @@ public function canRead(string $pFilename): bool
 
     /**
      * Does a file support UnserializePhpPresentation ?
-     *
-     * @throws FileNotFoundException
      */
     public function fileSupportsUnserializePhpPresentation(string $pFilename = ''): bool
     {
@@ -111,14 +113,12 @@ public function fileSupportsUnserializePhpPresentation(string $pFilename = ''):
 
     /**
      * Loads PhpPresentation Serialized file.
-     *
-     * @throws InvalidFileFormatException
      */
     public function load(string $pFilename): PhpPresentation
     {
         // Unserialize... First make sure the file supports it!
         if (!$this->fileSupportsUnserializePhpPresentation($pFilename)) {
-            throw new InvalidFileFormatException($pFilename, ODPresentation::class);
+            throw new InvalidFileFormatException($pFilename, self::class);
         }
 
         return $this->loadFile($pFilename);
@@ -157,7 +157,7 @@ protected function loadFile($pFilename)
     }
 
     /**
-     * Read Document Properties
+     * Read Document Properties.
      */
     protected function loadDocumentProperties(): void
     {
@@ -198,18 +198,22 @@ protected function loadDocumentProperties(): void
             switch ($propertyType) {
                 case 'boolean':
                     $propertyType = DocumentProperties::PROPERTY_TYPE_BOOLEAN;
+
                     break;
                 case 'float':
                     $propertyType = filter_var($propertyValue, FILTER_VALIDATE_INT) === false
                         ? DocumentProperties::PROPERTY_TYPE_FLOAT
                         : DocumentProperties::PROPERTY_TYPE_INTEGER;
+
                     break;
                 case 'date':
                     $propertyType = DocumentProperties::PROPERTY_TYPE_DATE;
+
                     break;
                 case 'string':
                 default:
                     $propertyType = DocumentProperties::PROPERTY_TYPE_STRING;
+
                     break;
             }
             $properties->setCustomProperty($propertyName, $propertyValue, $propertyType);
@@ -217,7 +221,7 @@ protected function loadDocumentProperties(): void
     }
 
     /**
-     * Extract all slides
+     * Extract all slides.
      */
     protected function loadSlides(): void
     {
@@ -244,7 +248,7 @@ protected function loadPresentationProperties(): void
     }
 
     /**
-     * Extract style
+     * Extract style.
      */
     protected function loadStyle(DOMElement $nodeStyle): bool
     {
@@ -306,6 +310,7 @@ protected function loadStyle(DOMElement $nodeStyle): bool
                     case 'none':
                         $oFill = new Fill();
                         $oFill->setFillType(Fill::FILL_NONE);
+
                         break;
                     case 'solid':
                         $oFill = new Fill();
@@ -315,6 +320,7 @@ protected function loadStyle(DOMElement $nodeStyle): bool
                             $oColor->setRGB(substr($nodeGraphicProps->getAttribute('draw:fill-color'), 1));
                             $oFill->setStartColor($oColor);
                         }
+
                         break;
                 }
             }
@@ -378,12 +384,15 @@ protected function loadStyle(DOMElement $nodeStyle): bool
                 switch ($nodeTextProperties->getAttribute('style:script-type')) {
                     case 'latin':
                         $oFont->setFormat(Font::FORMAT_LATIN);
+
                         break;
                     case 'asian':
                         $oFont->setFormat(Font::FORMAT_EAST_ASIAN);
+
                         break;
                     case 'complex':
                         $oFont->setFormat(Font::FORMAT_COMPLEX_SCRIPT);
+
                         break;
                 }
             }
@@ -414,11 +423,13 @@ protected function loadStyle(DOMElement $nodeStyle): bool
                     case 'tb-lr':
                     case 'lr':
                         $oAlignment->setIsRTL(false);
+
                         break;
                     case 'rl-tb':
                     case 'tb-rl':
                     case 'rl':
                         $oAlignment->setIsRTL(false);
+
                         break;
                     case 'tb':
                     case 'page':
@@ -487,7 +498,7 @@ protected function loadStyle(DOMElement $nodeStyle): bool
     }
 
     /**
-     * Read Slide
+     * Read Slide.
      */
     protected function loadSlide(DOMElement $nodeSlide): bool
     {
@@ -507,10 +518,12 @@ protected function loadSlide(DOMElement $nodeSlide): bool
             if ($oNodeFrame instanceof DOMElement) {
                 if ($this->oXMLReader->getElement('draw:image', $oNodeFrame)) {
                     $this->loadShapeDrawing($oNodeFrame);
+
                     continue;
                 }
                 if ($this->oXMLReader->getElement('draw:text-box', $oNodeFrame)) {
                     $this->loadShapeRichText($oNodeFrame);
+
                     continue;
                 }
             }
@@ -520,7 +533,7 @@ protected function loadSlide(DOMElement $nodeSlide): bool
     }
 
     /**
-     * Read Shape Drawing
+     * Read Shape Drawing.
      */
     protected function loadShapeDrawing(DOMElement $oNodeFrame): void
     {
@@ -577,7 +590,7 @@ protected function loadShapeDrawing(DOMElement $oNodeFrame): void
     }
 
     /**
-     * Read Shape RichText
+     * Read Shape RichText.
      */
     protected function loadShapeRichText(DOMElement $oNodeFrame): void
     {
@@ -608,7 +621,7 @@ protected function loadShapeRichText(DOMElement $oNodeFrame): void
     }
 
     /**
-     * Read Paragraph
+     * Read Paragraph.
      */
     protected function readParagraph(RichText $oShape, DOMElement $oNodeParent): void
     {
@@ -646,7 +659,7 @@ protected function readParagraph(RichText $oShape, DOMElement $oNodeParent): voi
     }
 
     /**
-     * Read Paragraph Item
+     * Read Paragraph Item.
      */
     protected function readParagraphItem(Paragraph $oParagraph, DOMElement $oNodeParent): void
     {
@@ -673,7 +686,7 @@ protected function readParagraphItem(Paragraph $oParagraph, DOMElement $oNodePar
     }
 
     /**
-     * Read List
+     * Read List.
      */
     protected function readList(RichText $oShape, DOMElement $oNodeParent): void
     {
@@ -692,7 +705,7 @@ protected function readList(RichText $oShape, DOMElement $oNodeParent): void
     }
 
     /**
-     * Read List Item
+     * Read List Item.
      */
     protected function readListItem(RichText $oShape, DOMElement $oNodeParent, DOMElement $oNodeParagraph): void
     {
@@ -726,11 +739,6 @@ protected function loadStylesFile(): void
         }
     }
 
-    /**
-     * @param string $expr
-     *
-     * @return string
-     */
     private function getExpressionUnit(string $expr): string
     {
         if (substr($expr, -1) == '%') {
@@ -740,11 +748,6 @@ private function getExpressionUnit(string $expr): string
         return substr($expr, -2);
     }
 
-    /**
-     * @param string $expr
-     *
-     * @return string
-     */
     private function getExpressionValue(string $expr): string
     {
         if (substr($expr, -1) == '%') {
diff --git a/src/PhpPresentation/Reader/PowerPoint2007.php b/src/PhpPresentation/Reader/PowerPoint2007.php
index ef065587cb..5ae4d03c46 100644
--- a/src/PhpPresentation/Reader/PowerPoint2007.php
+++ b/src/PhpPresentation/Reader/PowerPoint2007.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -66,24 +65,29 @@ class PowerPoint2007 implements ReaderInterface
      * @var PhpPresentation
      */
     protected $oPhpPresentation;
+
     /**
      * Output Object.
      *
-     * @var \ZipArchive
+     * @var ZipArchive
      */
     protected $oZip;
+
     /**
      * @var array<string, array<string, array<string, string>>>
      */
     protected $arrayRels = [];
+
     /**
      * @var SlideLayout[]
      */
     protected $arraySlideLayouts = [];
+
     /**
      * @var string
      */
     protected $filename;
+
     /**
      * @var string
      */
@@ -99,8 +103,6 @@ public function canRead(string $pFilename): bool
 
     /**
      * Does a file support UnserializePhpPresentation ?
-     *
-     * @throws FileNotFoundException
      */
     public function fileSupportsUnserializePhpPresentation(string $pFilename = ''): bool
     {
@@ -124,14 +126,12 @@ public function fileSupportsUnserializePhpPresentation(string $pFilename = ''):
 
     /**
      * Loads PhpPresentation Serialized file.
-     *
-     * @throws InvalidFileFormatException
      */
     public function load(string $pFilename): PhpPresentation
     {
         // Unserialize... First make sure the file supports it!
         if (!$this->fileSupportsUnserializePhpPresentation($pFilename)) {
-            throw new InvalidFileFormatException($pFilename, PowerPoint2007::class);
+            throw new InvalidFileFormatException($pFilename, self::class);
         }
 
         return $this->loadFile($pFilename);
@@ -184,7 +184,7 @@ protected function loadFile(string $pFilename): PhpPresentation
     protected function loadDocumentLayout(string $sPart): void
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             foreach ($xmlReader->getElements('/p:presentation/p:sldSz') as $oElement) {
                 if (!($oElement instanceof DOMElement)) {
@@ -211,7 +211,7 @@ protected function loadDocumentLayout(string $sPart): void
     protected function loadDocumentProperties(string $sPart): void
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             $arrayProperties = [
                 '/cp:coreProperties/dc:creator' => 'setCreator',
@@ -246,7 +246,7 @@ protected function loadCustomProperties(string $sPart): void
     {
         $xmlReader = new XMLReader();
         $sPart = str_replace(' xmlns="http://schemas.openxmlformats.org/officeDocument/2006/custom-properties"', '', $sPart);
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             foreach ($xmlReader->getElements('/Properties/property[@fmtid="{D5CDD505-2E9C-101B-9397-08002B2CF9AE}"]') as $element) {
                 if (!$element->hasAttribute('name')) {
@@ -289,12 +289,12 @@ protected function loadCustomProperties(string $sPart): void
     }
 
     /**
-     * Read Presentation Properties
+     * Read Presentation Properties.
      */
     protected function loadPresentationProperties(string $sPart): void
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             $element = $xmlReader->getElement('/p:presentationPr/p:showPr');
             if ($element instanceof DOMElement) {
@@ -328,25 +328,25 @@ protected function loadPresentationProperties(string $sPart): void
     protected function loadViewProperties(string $sPart): void
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             $pathZoom = '/p:viewPr/p:slideViewPr/p:cSldViewPr/p:cViewPr/p:scale/a:sx';
             $oElement = $xmlReader->getElement($pathZoom);
             if ($oElement instanceof DOMElement) {
                 if ($oElement->hasAttribute('d') && $oElement->hasAttribute('n')) {
-                    $this->oPhpPresentation->getPresentationProperties()->setZoom($oElement->getAttribute('n') / $oElement->getAttribute('d'));
+                    $this->oPhpPresentation->getPresentationProperties()->setZoom((int) $oElement->getAttribute('n') / (int) $oElement->getAttribute('d'));
                 }
             }
         }
     }
 
     /**
-     * Extract all slides
+     * Extract all slides.
      */
     protected function loadSlides(string $sPart): void
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             $fileRels = 'ppt/_rels/presentation.xml.rels';
             $this->loadRels($fileRels);
@@ -377,7 +377,7 @@ protected function loadSlides(string $sPart): void
     }
 
     /**
-     * Extract all MasterSlides
+     * Extract all MasterSlides.
      */
     protected function loadMasterSlides(XMLReader $xmlReader, string $fileRels): void
     {
@@ -401,12 +401,12 @@ protected function loadMasterSlides(XMLReader $xmlReader, string $fileRels): voi
     }
 
     /**
-     * Extract data from slide
+     * Extract data from slide.
      */
     protected function loadSlide(string $sPart, string $baseFile): void
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             // Core
             $oSlide = $this->oPhpPresentation->createSlide();
@@ -449,8 +449,8 @@ protected function loadSlide(string $sPart, string $baseFile): void
                         $pathImage = explode('/', $pathImage);
                         foreach ($pathImage as $key => $partPath) {
                             if ('..' == $partPath) {
-                                unset($pathImage[$key - 1]);
-                                unset($pathImage[$key]);
+                                unset($pathImage[$key - 1], $pathImage[$key]);
+
                             }
                         }
                         $pathImage = implode('/', $pathImage);
@@ -480,6 +480,7 @@ protected function loadSlide(string $sPart, string $baseFile): void
                     if (array_key_exists($layoutBasename, $this->arraySlideLayouts)) {
                         $oSlide->setSlideLayout($this->arraySlideLayouts[$layoutBasename]);
                     }
+
                     break;
                 }
             }
@@ -489,7 +490,7 @@ protected function loadSlide(string $sPart, string $baseFile): void
     protected function loadMasterSlide(string $sPart, string $baseFile): void
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             // Core
             $oSlideMaster = $this->oPhpPresentation->createMasterSlide();
@@ -533,7 +534,7 @@ protected function loadMasterSlide(string $sPart, string $baseFile): void
                     } else {
                         $level = str_replace('a:lvl', '', $oElementLvl->nodeName);
                         $level = str_replace('pPr', '', $level);
-                        $level = intval($level);
+                        $level = (int) $level;
                     }
 
                     if ($oElementLvl->hasAttribute('algn')) {
@@ -557,7 +558,7 @@ protected function loadMasterSlide(string $sPart, string $baseFile): void
                     $oElementLvlDefRPR = $xmlReader->getElement('a:defRPr', $oElementLvl);
                     if ($oElementLvlDefRPR instanceof DOMElement) {
                         if ($oElementLvlDefRPR->hasAttribute('sz')) {
-                            $oRTParagraph->getFont()->setSize((int) ($oElementLvlDefRPR->getAttribute('sz') / 100));
+                            $oRTParagraph->getFont()->setSize((int) ((int) $oElementLvlDefRPR->getAttribute('sz') / 100));
                         }
                         if ($oElementLvlDefRPR->hasAttribute('b') && 1 == $oElementLvlDefRPR->getAttribute('b')) {
                             $oRTParagraph->getFont()->setBold(true);
@@ -578,12 +579,15 @@ protected function loadMasterSlide(string $sPart, string $baseFile): void
                     switch ($oElementTxStyle->nodeName) {
                         case 'p:bodyStyle':
                             $oSlideMaster->getTextStyles()->setBodyStyleAtLvl($oRTParagraph, $level);
+
                             break;
                         case 'p:otherStyle':
                             $oSlideMaster->getTextStyles()->setOtherStyleAtLvl($oRTParagraph, $level);
+
                             break;
                         case 'p:titleStyle':
                             $oSlideMaster->getTextStyles()->setTitleStyleAtLvl($oRTParagraph, $level);
+
                             break;
                     }
                 }
@@ -596,6 +600,7 @@ protected function loadMasterSlide(string $sPart, string $baseFile): void
                     if (false !== $pptTheme) {
                         $this->loadTheme($pptTheme, $oSlideMaster);
                     }
+
                     break;
                 }
             }
@@ -625,7 +630,7 @@ protected function loadMasterSlide(string $sPart, string $baseFile): void
     protected function loadLayoutSlide(string $sPart, string $baseFile, SlideMaster $oSlideMaster): ?SlideLayout
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             // Core
             $oSlideLayout = new SlideLayout($oSlideMaster);
@@ -660,14 +665,14 @@ protected function loadLayoutSlide(string $sPart, string $baseFile, SlideMaster
 
             return $oSlideLayout;
         }
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         return null;
     }
 
     protected function loadTheme(string $sPart, SlideMaster $oSlideMaster): void
     {
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             $oElements = $xmlReader->getElements('/a:theme/a:themeElements/a:clrScheme/*');
             foreach ($oElements as $oElement) {
@@ -726,8 +731,8 @@ protected function loadSlideBackground(XMLReader $xmlReader, DOMElement $oElemen
                 $pathImage = explode('/', $pathImage);
                 foreach ($pathImage as $key => $partPath) {
                     if ('..' == $partPath) {
-                        unset($pathImage[$key - 1]);
-                        unset($pathImage[$key]);
+                        unset($pathImage[$key - 1], $pathImage[$key]);
+
                     }
                 }
                 $pathImage = implode('/', $pathImage);
@@ -748,7 +753,7 @@ protected function loadSlideNote(string $baseFile, Slide $oSlide): void
     {
         $sPart = $this->oZip->getFromName('ppt/notesSlides/' . $baseFile);
         $xmlReader = new XMLReader();
-        /* @phpstan-ignore-next-line */
+        // @phpstan-ignore-next-line
         if ($xmlReader->getDomFromString($sPart)) {
             $oNote = $oSlide->getNote();
 
@@ -791,8 +796,8 @@ protected function loadShapeDrawing(XMLReader $document, DOMElement $node, Abstr
                 $pathImage = explode('/', $pathImage);
                 foreach ($pathImage as $key => $partPath) {
                     if ('..' == $partPath) {
-                        unset($pathImage[$key - 1]);
-                        unset($pathImage[$key]);
+                        unset($pathImage[$key - 1], $pathImage[$key]);
+
                     }
                 }
                 $pathImage = implode('/', $pathImage);
@@ -1115,20 +1120,20 @@ protected function loadParagraph(XMLReader $document, DOMElement $oElement, $oSh
             $oElementLineSpacingPoints = $document->getElement('a:lnSpc/a:spcPts', $oSubElement);
             if ($oElementLineSpacingPoints instanceof DOMElement) {
                 $oParagraph->setLineSpacingMode(Paragraph::LINE_SPACING_MODE_POINT);
-                $oParagraph->setLineSpacing($oElementLineSpacingPoints->getAttribute('val') / 100);
+                $oParagraph->setLineSpacing((int) $oElementLineSpacingPoints->getAttribute('val') / 100);
             }
             $oElementLineSpacingPercent = $document->getElement('a:lnSpc/a:spcPct', $oSubElement);
             if ($oElementLineSpacingPercent instanceof DOMElement) {
                 $oParagraph->setLineSpacingMode(Paragraph::LINE_SPACING_MODE_PERCENT);
-                $oParagraph->setLineSpacing($oElementLineSpacingPercent->getAttribute('val') / 1000);
+                $oParagraph->setLineSpacing((int) $oElementLineSpacingPercent->getAttribute('val') / 1000);
             }
             $oElementSpacingBefore = $document->getElement('a:spcBef/a:spcPts', $oSubElement);
             if ($oElementSpacingBefore instanceof DOMElement) {
-                $oParagraph->setSpacingBefore($oElementSpacingBefore->getAttribute('val') / 100);
+                $oParagraph->setSpacingBefore((int) $oElementSpacingBefore->getAttribute('val') / 100);
             }
             $oElementSpacingAfter = $document->getElement('a:spcAft/a:spcPts', $oSubElement);
             if ($oElementSpacingAfter instanceof DOMElement) {
-                $oParagraph->setSpacingAfter($oElementSpacingAfter->getAttribute('val') / 100);
+                $oParagraph->setSpacingAfter((int) $oElementSpacingAfter->getAttribute('val') / 100);
             }
 
             $oParagraph->getBulletStyle()->setBulletType(Bullet::TYPE_NONE);
@@ -1194,7 +1199,7 @@ protected function loadParagraph(XMLReader $document, DOMElement $oElement, $oSh
                         $oText->getFont()->setStrikethrough('noStrike' == $oElementrPr->getAttribute('strike') ? false : true);
                     }
                     if ($oElementrPr->hasAttribute('sz')) {
-                        $oText->getFont()->setSize((int) ($oElementrPr->getAttribute('sz') / 100));
+                        $oText->getFont()->setSize((int) ((int) $oElementrPr->getAttribute('sz') / 100));
                     }
                     if ($oElementrPr->hasAttribute('u')) {
                         $oText->getFont()->setUnderline($oElementrPr->getAttribute('u'));
@@ -1264,7 +1269,7 @@ protected function loadHyperlink(XMLReader $xmlReader, DOMElement $element, Hype
     protected function loadStyleBorder(XMLReader $xmlReader, DOMElement $oElement, Border $oBorder): void
     {
         if ($oElement->hasAttribute('w')) {
-            $oBorder->setLineWidth((int) ($oElement->getAttribute('w') / 12700));
+            $oBorder->setLineWidth((int) ((int) $oElement->getAttribute('w') / 12700));
         }
         if ($oElement->hasAttribute('cmpd')) {
             $oBorder->setLineStyle($oElement->getAttribute('cmpd'));
@@ -1292,7 +1297,7 @@ protected function loadStyleColor(XMLReader $xmlReader, DOMElement $oElement): C
         $oColor->setRGB($oElement->getAttribute('val'));
         $oElementAlpha = $xmlReader->getElement('a:alpha', $oElement);
         if ($oElementAlpha instanceof DOMElement && $oElementAlpha->hasAttribute('val')) {
-            $alpha = strtoupper(dechex((($oElementAlpha->getAttribute('val') / 1000) / 100) * 255));
+            $alpha = strtoupper(dechex((((int) $oElementAlpha->getAttribute('val') / 1000) / 100) * 255));
             $oColor->setRGB($oElement->getAttribute('val'), $alpha);
         }
 
@@ -1347,7 +1352,7 @@ protected function loadRels(string $fileRels): void
         $sPart = $this->oZip->getFromName($fileRels);
         if (false !== $sPart) {
             $xmlReader = new XMLReader();
-            /* @phpstan-ignore-next-line */
+            // @phpstan-ignore-next-line
             if ($xmlReader->getDomFromString($sPart)) {
                 foreach ($xmlReader->getElements('*') as $oNode) {
                     if (!($oNode instanceof DOMElement)) {
@@ -1366,8 +1371,6 @@ protected function loadRels(string $fileRels): void
      * @param AbstractSlide|Note $oSlide
      * @param DOMNodeList<DOMNode> $oElements
      *
-     * @throws FeatureNotImplementedException
-     *
      * @internal param $baseFile
      */
     protected function loadSlideShapes($oSlide, DOMNodeList $oElements, XMLReader $xmlReader): void
@@ -1379,12 +1382,15 @@ protected function loadSlideShapes($oSlide, DOMNodeList $oElements, XMLReader $x
             switch ($oNode->tagName) {
                 case 'p:graphicFrame':
                     $this->loadShapeTable($xmlReader, $oNode, $oSlide);
+
                     break;
                 case 'p:pic':
                     $this->loadShapeDrawing($xmlReader, $oNode, $oSlide);
+
                     break;
                 case 'p:sp':
                     $this->loadShapeRichText($xmlReader, $oNode, $oSlide);
+
                     break;
                 default:
                     //throw new FeatureNotImplementedException();
diff --git a/src/PhpPresentation/Reader/PowerPoint97.php b/src/PhpPresentation/Reader/PowerPoint97.php
index b28b9fa4f1..94a60416db 100644
--- a/src/PhpPresentation/Reader/PowerPoint97.php
+++ b/src/PhpPresentation/Reader/PowerPoint97.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -299,85 +298,99 @@ class PowerPoint97 implements ReaderInterface
      * @var array<int, string>
      */
     private $arrayFonts = [];
+
     /**
      * Array with Hyperlinks.
      *
      * @var array<int, array<string, string>>
      */
     private $arrayHyperlinks = [];
+
     /**
      * Array with Notes.
      *
      * @var array<int, int>
      */
     private $arrayNotes = [];
+
     /**
      * Array with Pictures.
      *
      * @var array<int, string>
      */
     private $arrayPictures = [];
+
     /**
      * Offset (in bytes) from the beginning of the PowerPoint Document Stream to the UserEditAtom record for the most recent user edit.
      *
      * @var int
      */
     private $offsetToCurrentEdit;
+
     /**
      * A structure that specifies a compressed table of sequential persist object identifiers and stream offsets to associated persist objects.
      *
      * @var array<int, int>
      */
     private $rgPersistDirEntry;
+
     /**
      * Offset (in bytes) from the beginning of the PowerPoint Document Stream to the PersistDirectoryAtom record for this user edit.
      *
      * @var int
      */
     private $offsetPersistDirectory;
+
     /**
      * Output Object.
      *
      * @var PhpPresentation
      */
     private $oPhpPresentation;
+
     /**
-     * @var Group|null
+     * @var null|Group
      */
     private $oCurrentGroup;
+
     /**
      * @var bool
      */
     private $bFirstShapeGroup = false;
+
     /**
      * Stream "Powerpoint Document".
      *
      * @var string
      */
     private $streamPowerpointDocument;
+
     /**
      * Stream "Current User".
      *
      * @var string
      */
     private $streamCurrentUser;
+
     /**
      * Stream "Pictures".
      *
      * @var string
      */
     private $streamPictures;
+
     /**
      * @var int
      */
     private $inMainType;
+
     /**
-     * @var int|null
+     * @var null|int
      */
     private $currentNote;
 
     /**
-     * @var string|null
+     * @var null|string
      */
     private $filename;
 
@@ -391,8 +404,6 @@ public function canRead(string $pFilename): bool
 
     /**
      * Does a file support UnserializePhpPresentation ?
-     *
-     * @throws FileNotFoundException
      */
     public function fileSupportsUnserializePhpPresentation(string $pFilename = ''): bool
     {
@@ -415,14 +426,12 @@ public function fileSupportsUnserializePhpPresentation(string $pFilename = ''):
 
     /**
      * Loads PhpPresentation Serialized file.
-     *
-     * @throws InvalidFileFormatException
      */
     public function load(string $pFilename): PhpPresentation
     {
         // Unserialize... First make sure the file supports it!
         if (!$this->fileSupportsUnserializePhpPresentation($pFilename)) {
-            throw new InvalidFileFormatException($pFilename, PowerPoint97::class);
+            throw new InvalidFileFormatException($pFilename, self::class);
         }
 
         $this->filename = $pFilename;
@@ -431,7 +440,7 @@ public function load(string $pFilename): PhpPresentation
     }
 
     /**
-     * Load PhpPresentation Serialized file
+     * Load PhpPresentation Serialized file.
      */
     private function loadFile(): PhpPresentation
     {
@@ -451,7 +460,7 @@ private function loadFile(): PhpPresentation
     }
 
     /**
-     * Read OLE Part
+     * Read OLE Part.
      */
     private function loadOLE(): void
     {
@@ -472,8 +481,6 @@ private function loadOLE(): void
     /**
      * Stream Pictures.
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see http://msdn.microsoft.com/en-us/library/dd920746(v=office.12).aspx
      */
     private function loadPicturesStream(): void
@@ -491,12 +498,11 @@ private function loadPicturesStream(): void
                     // OfficeArtFBSE
                     throw new FeatureNotImplementedException();
                 }
-                if ($arrayRH['recType'] >= 0xF018 && $arrayRH['recType'] <= 0xF117) {
-                    $arrayRecord = $this->readRecordOfficeArtBlip($stream, $pos - 8);
-                    if ($arrayRecord['length'] > 0) {
-                        $pos += $arrayRecord['length'];
-                        $this->arrayPictures[] = $arrayRecord['picture'];
-                    }
+                // $arrayRH['recType'] >= 0xF018 && $arrayRH['recType'] <= 0xF117
+                $arrayRecord = $this->readRecordOfficeArtBlip($stream, $pos - 8);
+                if ($arrayRecord['length'] > 0) {
+                    $pos += $arrayRecord['length'];
+                    $this->arrayPictures[] = $arrayRecord['picture'];
                 }
                 $readSuccess = true;
             }
@@ -506,9 +512,6 @@ private function loadPicturesStream(): void
     /**
      * Stream Current User.
      *
-     * @throws FeatureNotImplementedException
-     * @throws InvalidFileFormatException
-     *
      * @see http://msdn.microsoft.com/en-us/library/dd908567(v=office.12).aspx
      */
     private function loadCurrentUserStream(): void
@@ -522,20 +525,20 @@ private function loadCurrentUserStream(): void
         $rHeader = $this->loadRecordHeader($this->streamCurrentUser, $pos);
         $pos += 8;
         if (0x0 != $rHeader['recVer'] || 0x000 != $rHeader['recInstance'] || self::RT_CURRENTUSERATOM != $rHeader['recType']) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : CurrentUserAtom > RecordHeader');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : CurrentUserAtom > RecordHeader');
         }
 
         // Size
         $size = self::getInt4d($this->streamCurrentUser, $pos);
         $pos += 4;
         if (0x00000014 != $size) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : CurrentUserAtom > Size');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : CurrentUserAtom > Size');
         }
 
         // headerToken
         $headerToken = self::getInt4d($this->streamCurrentUser, $pos);
         $pos += 4;
-        if (0xF3D1C4DF == $headerToken && 0xE391C05F != $headerToken) {
+        if (0xF3D1C4DF == $headerToken) {
             // Encrypted file
             throw new FeatureNotImplementedException();
         }
@@ -548,28 +551,28 @@ private function loadCurrentUserStream(): void
         $lenUserName = self::getInt2d($this->streamCurrentUser, $pos);
         $pos += 2;
         if ($lenUserName > 255) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : CurrentUserAtom > lenUserName');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : CurrentUserAtom > lenUserName');
         }
 
         // docFileVersion
         $docFileVersion = self::getInt2d($this->streamCurrentUser, $pos);
         $pos += 2;
         if (0x03F4 != $docFileVersion) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : CurrentUserAtom > docFileVersion');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : CurrentUserAtom > docFileVersion');
         }
 
         // majorVersion
         $majorVersion = self::getInt1d($this->streamCurrentUser, $pos);
         ++$pos;
         if (0x03 != $majorVersion) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : CurrentUserAtom > majorVersion');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : CurrentUserAtom > majorVersion');
         }
 
         // minorVersion
         $minorVersion = self::getInt1d($this->streamCurrentUser, $pos);
         ++$pos;
         if (0x00 != $minorVersion) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : CurrentUserAtom > minorVersion');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : CurrentUserAtom > minorVersion');
         }
 
         // unused
@@ -591,7 +594,7 @@ private function loadCurrentUserStream(): void
         $relVersion = self::getInt4d($this->streamCurrentUser, $pos);
         $pos += 4;
         if (0x00000008 != $relVersion && 0x00000009 != $relVersion) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : CurrentUserAtom > relVersion');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : CurrentUserAtom > relVersion');
         }
 
         // unicodeUserName
@@ -627,12 +630,15 @@ private function loadPowerpointDocumentStream(): void
             switch ($rHeader['recType']) {
                 case self::RT_DOCUMENT:
                     $this->readRecordDocumentContainer($this->streamPowerpointDocument, $pos);
+
                     break;
                 case self::RT_NOTES:
                     $this->readRecordNotesContainer($this->streamPowerpointDocument, $pos);
+
                     break;
                 case self::RT_SLIDE:
                     $this->readRecordSlideContainer($this->streamPowerpointDocument, $pos);
+
                     break;
                 default:
                     break;
@@ -699,8 +705,6 @@ public static function getInt4d(string $data, int $pos): int
      *
      * @return array<string, int>
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd772900(v=office.12).aspx
      */
     private function readRecordAnimationInfoContainer(string $stream, int $pos): array
@@ -724,9 +728,6 @@ private function readRecordAnimationInfoContainer(string $stream, int $pos): arr
     /**
      * A container record that specifies information about the document.
      *
-     * @throws FeatureNotImplementedException
-     * @throws InvalidFileFormatException
-     *
      * @see http://msdn.microsoft.com/en-us/library/dd947357(v=office.12).aspx
      */
     private function readRecordDocumentContainer(string $stream, int $pos): void
@@ -734,7 +735,7 @@ private function readRecordDocumentContainer(string $stream, int $pos): void
         $documentAtom = $this->loadRecordHeader($stream, $pos);
         $pos += 8;
         if (0x1 != $documentAtom['recVer'] || 0x000 != $documentAtom['recInstance'] || self::RT_DOCUMENTATOM != $documentAtom['recType']) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : RTDocument > DocumentAtom');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : RTDocument > DocumentAtom');
         }
         $pos += $documentAtom['recLen'];
 
@@ -744,7 +745,7 @@ private function readRecordDocumentContainer(string $stream, int $pos): void
             // exObjListAtom > rh
             $exObjListAtom = $this->loadRecordHeader($stream, $pos);
             if (0x0 != $exObjListAtom['recVer'] || 0x000 != $exObjListAtom['recInstance'] || self::RT_EXTERNALOBJECTLISTATOM != $exObjListAtom['recType'] || 0x00000004 != $exObjListAtom['recLen']) {
-                throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : RTDocument > DocumentAtom > exObjList > exObjListAtom');
+                throw new InvalidFileFormatException($this->filename, self::class, 'Location : RTDocument > DocumentAtom > exObjList > exObjListAtom');
             }
             $pos += 8;
             // exObjListAtom > exObjIdSeed
@@ -760,8 +761,8 @@ private function readRecordDocumentContainer(string $stream, int $pos): void
                         //@link : http://msdn.microsoft.com/en-us/library/dd944995(v=office.12).aspx
                         // exHyperlinkAtom > rh
                         $exHyperlinkAtom = $this->loadRecordHeader($stream, $pos);
-                        if (0x0 != $exHyperlinkAtom['recVer'] || 0x000 != $exHyperlinkAtom['recInstance'] || self::RT_EXTERNALHYPERLINKATOM != $exHyperlinkAtom['recType'] || 0x00000004 != $exObjListAtom['recLen']) {
-                            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : RTDocument > DocumentAtom > exObjList > rgChildRec > RT_ExternalHyperlink');
+                        if (0x0 != $exHyperlinkAtom['recVer'] || 0x000 != $exHyperlinkAtom['recInstance'] || self::RT_EXTERNALHYPERLINKATOM != $exHyperlinkAtom['recType'] || 0x00000004 != $exHyperlinkAtom['recLen']) {
+                            throw new InvalidFileFormatException($this->filename, self::class, 'Location : RTDocument > DocumentAtom > exObjList > rgChildRec > RT_ExternalHyperlink');
                         }
                         $pos += 8;
                         $exObjList['recLen'] -= 8;
@@ -810,6 +811,7 @@ private function readRecordDocumentContainer(string $stream, int $pos): void
                                 $string .= chr($char);
                             }
                         }
+
                         break;
                     default:
                         // var_dump(dechex((int) $childRec['recType']));
@@ -838,7 +840,7 @@ private function readRecordDocumentContainer(string $stream, int $pos): void
                     $pos += 8;
                     $fontCollection['recLen'] -= 8;
                     if (0x0 != $fontEntityAtom['recVer'] || $fontEntityAtom['recInstance'] > 128 || self::RT_FONTENTITYATOM != $fontEntityAtom['recType']) {
-                        throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : RTDocument > RT_Environment > RT_FontCollection > RT_FontEntityAtom');
+                        throw new InvalidFileFormatException($this->filename, self::class, 'Location : RTDocument > RT_Environment > RT_FontCollection > RT_FontEntityAtom');
                     }
                     $string = '';
                     for ($inc = 0; $inc < 32; ++$inc) {
@@ -1180,8 +1182,6 @@ private function readRecordMouseClickInteractiveInfoContainer(string $stream, in
      *
      * @return array<string, int>
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd925811(v=office.12).aspx
      */
     private function readRecordMouseOverInteractiveInfoContainer(string $stream, int $pos): array
@@ -1207,8 +1207,6 @@ private function readRecordMouseOverInteractiveInfoContainer(string $stream, int
      *
      * @return array{'length': int, 'picture': null|string}
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd910081(v=office.12).aspx
      */
     private function readRecordOfficeArtBlip(string $stream, int $pos): array
@@ -1240,6 +1238,7 @@ private function readRecordOfficeArtBlip(string $stream, int $pos): array
                     // BLIPFileData
                     $arrayReturn['picture'] = substr($this->streamPictures, $pos + $arrayReturn['length'], $data['recLen']);
                     $arrayReturn['length'] += $data['recLen'];
+
                     break;
                 default:
                     // var_dump(dechex((int) $data['recType']))
@@ -1286,8 +1285,6 @@ private function readRecordOfficeArtChildAnchor(string $stream, int $pos)
      *
      * @return array<string, int>
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd922797(v=office.12).aspx
      */
     private function readRecordOfficeArtClientAnchor(string $stream, int $pos)
@@ -1312,6 +1309,7 @@ private function readRecordOfficeArtClientAnchor(string $stream, int $pos)
                     $arrayReturn['height'] = (int) (self::getInt2d($stream, $pos + $arrayReturn['length']) / 6) - $arrayReturn['left'];
                     $arrayReturn['length'] += 2;
                     $pos += 8;
+
                     break;
                 case 0x00000010:
                     // record OfficeArtClientAnchor (0x00000010)
@@ -1327,8 +1325,6 @@ private function readRecordOfficeArtClientAnchor(string $stream, int $pos)
      *
      * @return array{'length': int, 'alignH': string|null, 'text': string, 'numParts': int, 'numTexts': int, 'hyperlink': array<int, array<string, int>>, 'part': array{'length': int, 'strLenRT': int, 'partLength': int|float, 'bold': bool, 'italic': bool, 'underline': bool, 'fontName': string, 'fontSize': int, 'color': Color}}
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd910958(v=office.12).aspx
      */
     private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
@@ -1352,9 +1348,7 @@ private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
             $strLen = 0;
             do {
                 $rhChild = $this->loadRecordHeader($stream, $pos + $arrayReturn['length']);
-                /*
-                 * @link : https://msdn.microsoft.com/en-us/library/dd947039(v=office.12).aspx
-                 */
+                // @link : https://msdn.microsoft.com/en-us/library/dd947039(v=office.12).aspx
                 // echo dechex($rhChild['recType']).'-'.$rhChild['recType'].EOL;
                 switch ($rhChild['recType']) {
                     case self::RT_INTERACTIVEINFO:
@@ -1368,6 +1362,7 @@ private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
                             $mouseOverInfo = $this->readRecordMouseOverInteractiveInfoContainer($stream, $pos + $arrayReturn['length']);
                             $arrayReturn['length'] += $mouseOverInfo['length'];
                         }
+
                         break;
                     case self::RT_STYLETEXTPROPATOM:
                         $arrayReturn['length'] += 8;
@@ -1393,6 +1388,7 @@ private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
                             $strLenRT = $strucTextCFRun['strLenRT'];
                             $arrayReturn['length'] += $strucTextCFRun['length'];
                         } while ($strLenRT > 0);
+
                         break;
                     case self::RT_TEXTBYTESATOM:
                         $arrayReturn['length'] += 8;
@@ -1406,6 +1402,7 @@ private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
                             $arrayReturn['text'] .= Text::chr($char);
                             ++$arrayReturn['length'];
                         }
+
                         break;
                     case self::RT_TEXTCHARSATOM:
                         $arrayReturn['length'] += 8;
@@ -1419,12 +1416,14 @@ private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
                             $arrayReturn['text'] .= Text::chr($char);
                             $arrayReturn['length'] += 2;
                         }
+
                         break;
                     case self::RT_TEXTHEADERATOM:
                         $arrayReturn['length'] += 8;
                         // @link : http://msdn.microsoft.com/en-us/library/dd905272(v=office.12).aspx
                         // textType
                         $arrayReturn['length'] += 4;
+
                         break;
                     case self::RT_TEXTINTERACTIVEINFOATOM:
                         $arrayReturn['length'] += 8;
@@ -1440,6 +1439,7 @@ private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
                         if (0x0001 == $rhChild['recInstance']) {
                             throw new FeatureNotImplementedException();
                         }
+
                         break;
                     case self::RT_TEXTSPECIALINFOATOM:
                         $arrayReturn['length'] += 8;
@@ -1450,16 +1450,19 @@ private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
                             $strLenRT = $structTextSIRun['strLenRT'];
                             $arrayReturn['length'] += $structTextSIRun['length'];
                         } while ($strLenRT > 0);
+
                         break;
                     case self::RT_TEXTRULERATOM:
                         $arrayReturn['length'] += 8;
                         // @link : http://msdn.microsoft.com/en-us/library/dd953212(v=office.12).aspx
                         $structRuler = $this->readStructureTextRuler($stream, $pos + $arrayReturn['length']);
                         $arrayReturn['length'] += $structRuler['length'];
+
                         break;
                     case self::RT_SLIDENUMBERMETACHARATOM:
                         $datasRecord = $this->readRecordSlideNumberMCAtom($stream, $pos + $arrayReturn['length']);
                         $arrayReturn['length'] += $datasRecord['length'];
+
                         break;
                     default:
                         $arrayReturn['length'] += 8;
@@ -1476,8 +1479,6 @@ private function readRecordOfficeArtClientTextbox(string $stream, int $pos)
      *
      * @return array{'length': int, 'shape': null|AbstractShape}
      *
-     * @throws InvalidFileFormatException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd943794(v=office.12).aspx
      */
     private function readRecordOfficeArtSpContainer(string $stream, int $pos)
@@ -1498,7 +1499,7 @@ private function readRecordOfficeArtSpContainer(string $stream, int $pos)
             // shapeProp
             $shapeProp = $this->readRecordOfficeArtFSP($stream, $pos + $arrayReturn['length']);
             if (0 == $shapeProp['length']) {
-                throw new InvalidFileFormatException($this->filename, PowerPoint97::class);
+                throw new InvalidFileFormatException($this->filename, self::class);
             }
             $arrayReturn['length'] += $shapeProp['length'];
 
@@ -1594,7 +1595,7 @@ private function readRecordOfficeArtSpContainer(string $stream, int $pos)
                     $start = 0;
                     $lastLevel = -1;
                     $lastMarginLeft = 0;
-                    /* @phpstan-ignore-next-line */
+                    // @phpstan-ignore-next-line
                     for ($inc = 1; $inc <= $clientTextbox['numParts']; ++$inc) {
                         if ($clientTextbox['numParts'] == $clientTextbox['numTexts'] && isset($clientTextbox['text' . $inc])) {
                             if (isset($clientTextbox['text' . $inc]['bulletChar'])) {
@@ -1621,7 +1622,7 @@ private function readRecordOfficeArtSpContainer(string $stream, int $pos)
                             }
                         }
                         // Texte
-                        $sText = substr(isset($clientTextbox['text']) ? $clientTextbox['text'] : '', $start, $clientTextbox['part' . $inc]['partLength']);
+                        $sText = substr($clientTextbox['text'] ?? '', $start, $clientTextbox['part' . $inc]['partLength']);
                         $sHyperlinkURL = '';
                         if (empty($sText)) {
                             // Is there a hyperlink ?
@@ -1630,6 +1631,7 @@ private function readRecordOfficeArtSpContainer(string $stream, int $pos)
                                     if ($itmHyperlink['start'] == $start && ($itmHyperlink['end'] - $itmHyperlink['start']) == (float) $clientTextbox['part' . $inc]['partLength']) {
                                         $sText = $this->arrayHyperlinks[$itmHyperlink['id']]['text'];
                                         $sHyperlinkURL = $this->arrayHyperlinks[$itmHyperlink['id']]['url'];
+
                                         break;
                                     }
                                 }
@@ -1746,8 +1748,6 @@ private function readRecordOfficeArtSpContainer(string $stream, int $pos)
      *
      * @return array<string, int>
      *
-     * @throws InvalidFileFormatException
-     *
      * @see : https://msdn.microsoft.com/en-us/library/dd910416(v=office.12).aspx
      */
     private function readRecordOfficeArtSpgrContainer($stream, $pos, $bInGroup = false)
@@ -1763,7 +1763,7 @@ private function readRecordOfficeArtSpgrContainer($stream, $pos, $bInGroup = fal
             do {
                 $rhFileBlock = $this->loadRecordHeader($stream, $pos + $arrayReturn['length']);
                 if (!(0xF == $rhFileBlock['recVer'] && 0x0000 == $rhFileBlock['recInstance'] && (0xF003 == $rhFileBlock['recType'] || 0xF004 == $rhFileBlock['recType']))) {
-                    throw new InvalidFileFormatException($this->filename, PowerPoint97::class);
+                    throw new InvalidFileFormatException($this->filename, self::class);
                 }
 
                 switch ($rhFileBlock['recType']) {
@@ -1775,6 +1775,7 @@ private function readRecordOfficeArtSpgrContainer($stream, $pos, $bInGroup = fal
                         $fileBlock = $this->readRecordOfficeArtSpgrContainer($stream, $pos + $arrayReturn['length'], true);
                         $arrayReturn['length'] += $fileBlock['length'];
                         $data['recLen'] -= $fileBlock['length'];
+
                         break;
                     case 0xF004:
                         // Core
@@ -1787,7 +1788,7 @@ private function readRecordOfficeArtSpgrContainer($stream, $pos, $bInGroup = fal
                         $data['recLen'] -= $fileBlock['length'];
                         // Core
                         //@todo
-                        if (!is_null($fileBlock['shape'])) {
+                        if (null !== $fileBlock['shape']) {
                             switch ($this->inMainType) {
                                 case self::RT_NOTES:
                                     $arrayIdxSlide = array_flip($this->arrayNotes);
@@ -1797,6 +1798,7 @@ private function readRecordOfficeArtSpgrContainer($stream, $pos, $bInGroup = fal
                                             $oSlide->getNote()->addShape($fileBlock['shape']);
                                         }
                                     }
+
                                     break;
                                 case self::RT_SLIDE:
                                     if ($bInGroup) {
@@ -1804,6 +1806,7 @@ private function readRecordOfficeArtSpgrContainer($stream, $pos, $bInGroup = fal
                                     } else {
                                         $this->oPhpPresentation->getActiveSlide()->addShape($fileBlock['shape']);
                                     }
+
                                     break;
                             }
                         }
@@ -1821,8 +1824,6 @@ private function readRecordOfficeArtSpgrContainer($stream, $pos, $bInGroup = fal
      *
      * @return array<string, int>
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd950206(v=office.12).aspx
      */
     private function readRecordOfficeArtTertiaryFOPT(string $stream, int $pos)
@@ -1862,6 +1863,7 @@ private function readRecordOfficeArtTertiaryFOPT(string $stream, int $pos)
                         if (0x1 == $opt['fComplex']) {
                             $arrayReturn['length'] += $opt['op'];
                         }
+
                         break;
                     case 0x03A9:
                         // GroupShape : metroBlob
@@ -1869,6 +1871,7 @@ private function readRecordOfficeArtTertiaryFOPT(string $stream, int $pos)
                         if (0x1 == $opt['fComplex']) {
                             $arrayReturn['length'] += $opt['op'];
                         }
+
                         break;
                     case 0x01FF:
                         // Line Style Boolean
@@ -1950,7 +1953,7 @@ private function readRecordOfficeArtFDG(string $stream, int $pos): array
     /**
      * The OfficeArtFOPT record specifies a table of OfficeArtRGFOPTE records.
      *
-     * @return array<string, int|string|bool>
+     * @return array<string, bool|int|string>
      *
      * @see https://msdn.microsoft.com/en-us/library/dd943404(v=office.12).aspx
      */
@@ -1989,6 +1992,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                         // Transform : rotation
                         //@link : https://msdn.microsoft.com/en-us/library/dd949750(v=office.12).aspx
                         $arrayReturn['rotation'] = $opt['op'];
+
                         break;
                     case 0x007F:
                         // Transform : Protection Boolean Properties
@@ -2002,21 +2006,25 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                         // Text : dxTextLeft
                         //@link : http://msdn.microsoft.com/en-us/library/dd953234(v=office.12).aspx
                         $arrayReturn['insetLeft'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
+
                         break;
                     case 0x0082:
                         // Text : dyTextTop
                         //@link : http://msdn.microsoft.com/en-us/library/dd925068(v=office.12).aspx
                         $arrayReturn['insetTop'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
+
                         break;
                     case 0x0083:
                         // Text : dxTextRight
                         //@link : http://msdn.microsoft.com/en-us/library/dd906782(v=office.12).aspx
                         $arrayReturn['insetRight'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
+
                         break;
                     case 0x0084:
                         // Text : dyTextBottom
                         //@link : http://msdn.microsoft.com/en-us/library/dd772858(v=office.12).aspx
                         $arrayReturn['insetBottom'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
+
                         break;
                     case 0x0085:
                         // Text : WrapText
@@ -2036,9 +2044,9 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                         if (0 == $opt['fComplex']) {
                             $arrayReturn['pib'] = $opt['op'];
                             $data['recLen'] -= $opt['op'];
-                        } else {
-                            // pib Complex
                         }
+                            // pib Complex
+
                         break;
                     case 0x13F:
                         // Blip Boolean Properties
@@ -2068,6 +2076,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                         // Geometry : shapePath
                         //@link : http://msdn.microsoft.com/en-us/library/dd945249(v=office.12).aspx
                         $arrayReturn['line'] = true;
+
                         break;
                     case 0x145:
                         // Geometry : pVertices
@@ -2076,6 +2085,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                             $arrayReturn['length'] += $opt['op'];
                             $data['recLen'] -= $opt['op'];
                         }
+
                         break;
                     case 0x146:
                         // Geometry : pSegmentInfo
@@ -2084,6 +2094,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                             $arrayReturn['length'] += $opt['op'];
                             $data['recLen'] -= $opt['op'];
                         }
+
                         break;
                     case 0x155:
                         // Geometry : pAdjustHandles
@@ -2092,6 +2103,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                             $arrayReturn['length'] += $opt['op'];
                             $data['recLen'] -= $opt['op'];
                         }
+
                         break;
                     case 0x156:
                         // Geometry : pGuides
@@ -2100,6 +2112,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                             $arrayReturn['length'] += $opt['op'];
                             $data['recLen'] -= $opt['op'];
                         }
+
                         break;
                     case 0x157:
                         // Geometry : pInscribe
@@ -2108,6 +2121,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                             $arrayReturn['length'] += $opt['op'];
                             $data['recLen'] -= $opt['op'];
                         }
+
                         break;
                     case 0x17F:
                         // Geometry Boolean Properties
@@ -2154,6 +2168,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                         $strColor .= str_pad(dechex(($opt['op'] >> 8) & bindec('11111111')), 2, '0', STR_PAD_LEFT);
                         $strColor .= str_pad(dechex(($opt['op'] >> 16) & bindec('11111111')), 2, '0', STR_PAD_LEFT);
                         $arrayReturn['lineColor'] = $strColor;
+
                         break;
                     case 0x01C1:
                         // Line Style : lineOpacity
@@ -2168,6 +2183,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                         // Line Style : lineWidth
                         //@link : http://msdn.microsoft.com/en-us/library/dd926964(v=office.12).aspx
                         $arrayReturn['lineWidth'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
+
                         break;
                     case 0x01D6:
                         // Line Style : lineJoinStyle
@@ -2193,11 +2209,13 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                         // Shadow Style : shadowOffsetX
                         //@link : http://msdn.microsoft.com/en-us/library/dd945280(v=office.12).aspx
                         $arrayReturn['shadowOffsetX'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
+
                         break;
                     case 0x0206:
                         // Shadow Style : shadowOffsetY
                         //@link : http://msdn.microsoft.com/en-us/library/dd907855(v=office.12).aspx
                         $arrayReturn['shadowOffsetY'] = \PhpOffice\Common\Drawing::emuToPixels((int) $opt['op']);
+
                         break;
                     case 0x023F:
                         // Shadow Style : Shadow Style Boolean Properties
@@ -2218,6 +2236,7 @@ private function readRecordOfficeArtFOPT(string $stream, int $pos): array
                             $arrayReturn['length'] += $opt['op'];
                             $data['recLen'] -= $opt['op'];
                         }
+
                         break;
                     case 0x03BF:
                         // Group Shape Property Set : Group Shape Boolean Properties
@@ -2344,8 +2363,6 @@ private function readRecordOfficeArtSecondaryFOPT(string $stream, int $pos): arr
      *
      * @return array<string, int>
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see : https://msdn.microsoft.com/en-us/library/dd950927(v=office.12).aspx
      */
     private function readRecordOfficeArtClientData(string $stream, int $pos): array
@@ -2404,14 +2421,17 @@ private function readRecordOfficeArtClientData(string $stream, int $pos): array
                         case self::RT_PROGTAGS:
                             $dataRG = $this->readRecordShapeProgTagsContainer($stream, $pos + $arrayReturn['length']);
                             $arrayReturn['length'] += $dataRG['length'];
+
                             break;
                         case self::RT_ROUNDTRIPHFPLACEHOLDER12ATOM:
                             $dataRG = $this->readRecordRoundTripHFPlaceholder12Atom($stream, $pos + $arrayReturn['length']);
                             $arrayReturn['length'] += $dataRG['length'];
+
                             break;
                         case self::RT_ROUNDTRIPSHAPEID12ATOM:
                             $dataRG = $this->readRecordRoundTripShapeId12Atom($stream, $pos + $arrayReturn['length']);
                             $arrayReturn['length'] += $dataRG['length'];
+
                             break;
                         default:
                             // var_dump('0x' . dechex($dataHeaderRG['recType']));
@@ -2428,15 +2448,13 @@ private function readRecordOfficeArtClientData(string $stream, int $pos): array
      * An atom record that specifies a persist object directory. Each persist object identifier specified MUST be unique in that persist object directory.
      *
      * @see http://msdn.microsoft.com/en-us/library/dd952680(v=office.12).aspx
-     *
-     * @throws InvalidFileFormatException
      */
     private function readRecordPersistDirectoryAtom(string $stream, int $pos): void
     {
         $rHeader = $this->loadRecordHeader($stream, $pos);
         $pos += 8;
         if (0x0 != $rHeader['recVer'] || 0x000 != $rHeader['recInstance'] || self::RT_PERSISTDIRECTORYATOM != $rHeader['recType']) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : PersistDirectoryAtom > RecordHeader');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : PersistDirectoryAtom > RecordHeader');
         }
         // rgPersistDirEntry
         // @link : http://msdn.microsoft.com/en-us/library/dd947347(v=office.12).aspx
@@ -2678,8 +2696,6 @@ private function readRecordShapeProgBinaryTagContainer(string $stream, int $pos)
      *
      * @return array<string, int>
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd911266(v=office.12).aspx
      */
     private function readRecordShapeProgTagsContainer(string $stream, int $pos): array
@@ -2700,6 +2716,7 @@ private function readRecordShapeProgTagsContainer(string $stream, int $pos): arr
                     case self::RT_PROGBINARYTAG:
                         $dataRG = $this->readRecordShapeProgBinaryTagContainer($stream, $pos + $arrayReturn['length'] + $length);
                         $length += $dataRG['length'];
+
                         break;
                     //case self::RT_PROGSTRINGTAG:
                     default:
@@ -2756,8 +2773,6 @@ private function readRecordSlideAtom(string $stream, int $pos): array
     /**
      * A container record that specifies a presentation slide or title master slide.
      *
-     * @throws InvalidFileFormatException
-     *
      * @see http://msdn.microsoft.com/en-us/library/dd946323(v=office.12).aspx
      */
     private function readRecordSlideContainer(string $stream, int $pos): void
@@ -2769,7 +2784,7 @@ private function readRecordSlideContainer(string $stream, int $pos): void
         // *** slideAtom (32 bytes)
         $slideAtom = $this->readRecordSlideAtom($stream, $pos);
         if (0 == $slideAtom['length']) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class);
+            throw new InvalidFileFormatException($this->filename, self::class);
         }
         $pos += $slideAtom['length'];
 
@@ -2793,7 +2808,7 @@ private function readRecordSlideContainer(string $stream, int $pos): void
         $slideSchemeColorAtom = $this->readRecordSlideSchemeColorSchemeAtom($stream, $pos);
         if (0 == $slideSchemeColorAtom['length']) {
             // Record SlideSchemeColorSchemeAtom
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class);
+            throw new InvalidFileFormatException($this->filename, self::class);
         }
         $pos += $slideSchemeColorAtom['length'];
 
@@ -2946,15 +2961,13 @@ private function readRecordSlideShowSlideInfoAtom(string $stream, int $pos): arr
      * UserEditAtom.
      *
      * @see http://msdn.microsoft.com/en-us/library/dd945746(v=office.12).aspx
-     *
-     * @throws InvalidFileFormatException
      */
     private function readRecordUserEditAtom(string $stream, int $pos): void
     {
         $rHeader = $this->loadRecordHeader($stream, $pos);
         $pos += 8;
         if (0x0 != $rHeader['recVer'] || 0x000 != $rHeader['recInstance'] || self::RT_USEREDITATOM != $rHeader['recType'] || (0x0000001C != $rHeader['recLen'] && 0x00000020 != $rHeader['recLen'])) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : UserEditAtom > RecordHeader');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : UserEditAtom > RecordHeader');
         }
 
         // lastSlideIdRef
@@ -2966,14 +2979,14 @@ private function readRecordUserEditAtom(string $stream, int $pos): void
         $minorVersion = self::getInt1d($stream, $pos);
         ++$pos;
         if (0x00 != $minorVersion) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : UserEditAtom > minorVersion');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : UserEditAtom > minorVersion');
         }
 
         // majorVersion
         $majorVersion = self::getInt1d($stream, $pos);
         ++$pos;
         if (0x03 != $majorVersion) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : UserEditAtom > majorVersion');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : UserEditAtom > majorVersion');
         }
 
         // offsetLastEdit
@@ -2986,7 +2999,7 @@ private function readRecordUserEditAtom(string $stream, int $pos): void
         $docPersistIdRef = self::getInt4d($stream, $pos);
         $pos += 4;
         if (0x00000001 != $docPersistIdRef) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : UserEditAtom > docPersistIdRef');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : UserEditAtom > docPersistIdRef');
         }
 
         // persistIdSeed
@@ -3002,8 +3015,6 @@ private function readRecordUserEditAtom(string $stream, int $pos): void
      *
      * @return array{'length': int, 'strLenRT': int, 'partLength': int, 'bold': bool, 'italic': bool, 'underline': bool, 'fontName': string, 'fontSize': int, 'color': Color}
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd945870(v=office.12).aspx
      */
     private function readStructureTextCFRun(string $stream, int $pos, int $strLenRT): array
@@ -3071,7 +3082,7 @@ private function readStructureTextCFRun(string $stream, int $pos, int $strLenRT)
         if (1 == $masksData['typeface']) {
             $data = self::getInt2d($stream, $pos + $arrayReturn['length']);
             $arrayReturn['length'] += 2;
-            $arrayReturn['fontName'] = isset($this->arrayFonts[$data]) ? $this->arrayFonts[$data] : '';
+            $arrayReturn['fontName'] = $this->arrayFonts[$data] ?? '';
         }
         if (1 == $masksData['oldEATypeface']) {
             // $data = self::getInt2d($stream, $pos + $arrayReturn['length']);
@@ -3119,8 +3130,6 @@ private function readStructureTextCFRun(string $stream, int $pos, int $strLenRT)
      *
      * @return array{'length': int, 'strLenRT': int, 'alignH': string|null, 'bulletChar': string, 'leftMargin': int, 'indent': int}
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd923535(v=office.12).aspx
      */
     private function readStructureTextPFRun(string $stream, int $pos, int $strLenRT): array
@@ -3214,24 +3223,31 @@ private function readStructureTextPFRun(string $stream, int $pos, int $strLenRT)
             switch ($data) {
                 case 0x0000:
                     $arrayReturn['alignH'] = Alignment::HORIZONTAL_LEFT;
+
                     break;
                 case 0x0001:
                     $arrayReturn['alignH'] = Alignment::HORIZONTAL_CENTER;
+
                     break;
                 case 0x0002:
                     $arrayReturn['alignH'] = Alignment::HORIZONTAL_RIGHT;
+
                     break;
                 case 0x0003:
                     $arrayReturn['alignH'] = Alignment::HORIZONTAL_JUSTIFY;
+
                     break;
                 case 0x0004:
                     $arrayReturn['alignH'] = Alignment::HORIZONTAL_DISTRIBUTED;
+
                     break;
                 case 0x0005:
                     $arrayReturn['alignH'] = Alignment::HORIZONTAL_DISTRIBUTED;
+
                     break;
                 case 0x0006:
                     $arrayReturn['alignH'] = Alignment::HORIZONTAL_JUSTIFY;
+
                     break;
                 default:
                     break;
@@ -3286,8 +3302,6 @@ private function readStructureTextPFRun(string $stream, int $pos, int $strLenRT)
      *
      * @return array<string, int>
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd909603(v=office.12).aspx
      */
     private function readStructureTextSIRun(string $stream, int $pos, int $strLenRT): array
@@ -3348,8 +3362,6 @@ private function readStructureTextSIRun(string $stream, int $pos, int $strLenRT)
      *
      * @return array<string, int>
      *
-     * @throws FeatureNotImplementedException
-     *
      * @see https://msdn.microsoft.com/en-us/library/dd922749(v=office.12).aspx
      */
     private function readStructureTextRuler(string $stream, int $pos): array
@@ -3459,8 +3471,6 @@ private function readRecordNotesContainer(string $stream, int $pos): void
 
     /**
      * @return array<string, int>
-     *
-     * @throws InvalidFileFormatException
      */
     private function readRecordNotesAtom(string $stream, int $pos): array
     {
@@ -3470,7 +3480,7 @@ private function readRecordNotesAtom(string $stream, int $pos): array
 
         $data = $this->loadRecordHeader($stream, $pos);
         if (0x1 != $data['recVer'] || 0x000 != $data['recInstance'] || self::RT_NOTESATOM != $data['recType'] || 0x00000008 != $data['recLen']) {
-            throw new InvalidFileFormatException($this->filename, PowerPoint97::class, 'Location : NotesAtom > RecordHeader)');
+            throw new InvalidFileFormatException($this->filename, self::class, 'Location : NotesAtom > RecordHeader)');
         }
         // Record Header
         $arrayReturn['length'] += 8;
diff --git a/src/PhpPresentation/Reader/ReaderInterface.php b/src/PhpPresentation/Reader/ReaderInterface.php
index d3e06d393c..e6a4c3ad5e 100644
--- a/src/PhpPresentation/Reader/ReaderInterface.php
+++ b/src/PhpPresentation/Reader/ReaderInterface.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Reader/Serialized.php b/src/PhpPresentation/Reader/Serialized.php
index 33de31b412..208c283255 100644
--- a/src/PhpPresentation/Reader/Serialized.php
+++ b/src/PhpPresentation/Reader/Serialized.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -43,8 +42,6 @@ public function canRead(string $pFilename): bool
 
     /**
      * Does a file support UnserializePhpPresentation ?
-     *
-     * @throws FileNotFoundException
      */
     public function fileSupportsUnserializePhpPresentation(string $pFilename): bool
     {
@@ -59,9 +56,6 @@ public function fileSupportsUnserializePhpPresentation(string $pFilename): bool
 
     /**
      * Loads PhpPresentation Serialized file.
-     *
-     * @throws FileNotFoundException
-     * @throws InvalidFileFormatException
      */
     public function load(string $pFilename): PhpPresentation
     {
@@ -72,7 +66,7 @@ public function load(string $pFilename): PhpPresentation
 
         // Unserialize... First make sure the file supports it!
         if (!$this->fileSupportsUnserializePhpPresentation($pFilename)) {
-            throw new InvalidFileFormatException($pFilename, Serialized::class);
+            throw new InvalidFileFormatException($pFilename, self::class);
         }
 
         return $this->loadSerialized($pFilename);
@@ -80,19 +74,17 @@ public function load(string $pFilename): PhpPresentation
 
     /**
      * Load PhpPresentation Serialized file.
-     *
-     * @throws InvalidFileFormatException
      */
     private function loadSerialized(string $pFilename): PhpPresentation
     {
         $oArchive = new ZipArchive();
         if (true !== $oArchive->open($pFilename)) {
-            throw new InvalidFileFormatException($pFilename, Serialized::class);
+            throw new InvalidFileFormatException($pFilename, self::class);
         }
 
         $xmlContent = $oArchive->getFromName('PhpPresentation.xml');
         if (empty($xmlContent)) {
-            throw new InvalidFileFormatException($pFilename, Serialized::class, 'The file PhpPresentation.xml is malformed');
+            throw new InvalidFileFormatException($pFilename, self::class, 'The file PhpPresentation.xml is malformed');
         }
 
         $xmlData = simplexml_load_string($xmlContent);
diff --git a/src/PhpPresentation/Shape/AbstractGraphic.php b/src/PhpPresentation/Shape/AbstractGraphic.php
index e7a4e731d7..f8b464f510 100644
--- a/src/PhpPresentation/Shape/AbstractGraphic.php
+++ b/src/PhpPresentation/Shape/AbstractGraphic.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -68,7 +67,7 @@ abstract class AbstractGraphic extends AbstractShape implements ComparableInterf
      *
      * @var string
      */
-    public $relationId = null;
+    public $relationId;
 
     /**
      * Create a new \PhpOffice\PhpPresentation\Slide\AbstractDrawing.
diff --git a/src/PhpPresentation/Shape/AutoShape.php b/src/PhpPresentation/Shape/AutoShape.php
index 3d2c21ca59..fc52bad918 100644
--- a/src/PhpPresentation/Shape/AutoShape.php
+++ b/src/PhpPresentation/Shape/AutoShape.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -25,7 +24,7 @@
 use PhpOffice\PhpPresentation\Style\Outline;
 
 /**
- * AutoShape shape
+ * AutoShape shape.
  *
  * @see : https://github.com/scanny/python-pptx/blob/eaa1e0fd3db28b03a353e116a5c7d2084dd87c26/pptx/enum/shapes.py
  */
@@ -238,19 +237,11 @@ public function __construct()
         $this->outline = new Outline();
     }
 
-    /**
-     * @return string
-     */
     public function getText(): string
     {
         return $this->text;
     }
 
-    /**
-     * @param string $text
-     *
-     * @return self
-     */
     public function setText(string $text): self
     {
         $this->text = $text;
@@ -258,19 +249,11 @@ public function setText(string $text): self
         return $this;
     }
 
-    /**
-     * @return string
-     */
     public function getType(): string
     {
         return $this->type;
     }
 
-    /**
-     * @param string $type
-     *
-     * @return self
-     */
     public function setType(string $type): self
     {
         $this->type = $type;
@@ -278,19 +261,11 @@ public function setType(string $type): self
         return $this;
     }
 
-    /**
-     * @return Outline
-     */
     public function getOutline(): Outline
     {
         return $this->outline;
     }
 
-    /**
-     * @param Outline $outline
-     *
-     * @return self
-     */
     public function setOutline(Outline $outline): self
     {
         $this->outline = $outline;
diff --git a/src/PhpPresentation/Shape/Chart.php b/src/PhpPresentation/Shape/Chart.php
index 3d56b7378e..35aa3d17ad 100644
--- a/src/PhpPresentation/Shape/Chart.php
+++ b/src/PhpPresentation/Shape/Chart.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -103,9 +102,7 @@ public function __clone()
     }
 
     /**
-     * How missing/blank values are displayed on chart (dispBlanksAs property)
-     *
-     * @return string
+     * How missing/blank values are displayed on chart (dispBlanksAs property).
      */
     public function getDisplayBlankAs(): string
     {
@@ -114,8 +111,6 @@ public function getDisplayBlankAs(): string
 
     /**
      * Get Title.
-     *
-     * @return Title
      */
     public function getTitle(): Title
     {
@@ -124,8 +119,6 @@ public function getTitle(): Title
 
     /**
      * Get Legend.
-     *
-     * @return Legend
      */
     public function getLegend(): Legend
     {
@@ -134,8 +127,6 @@ public function getLegend(): Legend
 
     /**
      * Get PlotArea.
-     *
-     * @return PlotArea
      */
     public function getPlotArea(): PlotArea
     {
@@ -144,8 +135,6 @@ public function getPlotArea(): PlotArea
 
     /**
      * Get View3D.
-     *
-     * @return View3D
      */
     public function getView3D(): View3D
     {
@@ -154,8 +143,6 @@ public function getView3D(): View3D
 
     /**
      * Is the spreadsheet included for editing data ?
-     *
-     * @return bool
      */
     public function hasIncludedSpreadsheet(): bool
     {
@@ -163,11 +150,7 @@ public function hasIncludedSpreadsheet(): bool
     }
 
     /**
-     * Define a way to display missing/blank values (dispBlanksAs property)
-     *
-     * @param string $value
-     *
-     * @return self
+     * Define a way to display missing/blank values (dispBlanksAs property).
      */
     public function setDisplayBlankAs(string $value): self
     {
@@ -180,10 +163,6 @@ public function setDisplayBlankAs(string $value): self
 
     /**
      * Is the spreadsheet included for editing data ?
-     *
-     * @param bool $value
-     *
-     * @return self
      */
     public function setIncludeSpreadsheet(bool $value = false): self
     {
@@ -194,8 +173,6 @@ public function setIncludeSpreadsheet(bool $value = false): self
 
     /**
      * Get indexed filename (using image index).
-     *
-     * @return string
      */
     public function getIndexedFilename(): string
     {
diff --git a/src/PhpPresentation/Shape/Chart/Axis.php b/src/PhpPresentation/Shape/Chart/Axis.php
index 86e1878708..f8588e903d 100644
--- a/src/PhpPresentation/Shape/Chart/Axis.php
+++ b/src/PhpPresentation/Shape/Chart/Axis.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -55,7 +54,7 @@ class Axis implements ComparableInterface
     private $titleRotation = 0;
 
     /**
-     * Format code
+     * Format code.
      *
      * @var string
      */
@@ -69,12 +68,12 @@ class Axis implements ComparableInterface
     private $font;
 
     /**
-     * @var Gridlines|null
+     * @var null|Gridlines
      */
     protected $majorGridlines;
 
     /**
-     * @var Gridlines|null
+     * @var null|Gridlines
      */
     protected $minorGridlines;
 
@@ -147,8 +146,6 @@ public function __construct(string $title = 'Axis Title')
 
     /**
      * Get Title.
-     *
-     * @return string
      */
     public function getTitle(): string
     {
@@ -157,10 +154,6 @@ public function getTitle(): string
 
     /**
      * Set Title.
-     *
-     * @param string $value
-     *
-     * @return self
      */
     public function setTitle(string $value = 'Axis Title'): self
     {
@@ -171,8 +164,6 @@ public function setTitle(string $value = 'Axis Title'): self
 
     /**
      * Get font.
-     *
-     * @return Font|null
      */
     public function getFont(): ?Font
     {
@@ -181,12 +172,8 @@ public function getFont(): ?Font
 
     /**
      * Set font.
-     *
-     * @param Font|null $font
-     *
-     * @return self
      */
-    public function setFont(Font $font = null): self
+    public function setFont(?Font $font = null): self
     {
         $this->font = $font;
 
@@ -195,8 +182,6 @@ public function setFont(Font $font = null): self
 
     /**
      * Get Format Code.
-     *
-     * @return string
      */
     public function getFormatCode(): string
     {
@@ -205,10 +190,6 @@ public function getFormatCode(): string
 
     /**
      * Set Format Code.
-     *
-     * @param string $value
-     *
-     * @return self
      */
     public function setFormatCode(string $value = ''): self
     {
@@ -217,59 +198,35 @@ public function setFormatCode(string $value = ''): self
         return $this;
     }
 
-    /**
-     * @return int|null
-     */
     public function getMinBounds(): ?int
     {
         return $this->minBounds;
     }
 
-    /**
-     * @param int|null $minBounds
-     *
-     * @return self
-     */
-    public function setMinBounds(int $minBounds = null): self
+    public function setMinBounds(?int $minBounds = null): self
     {
-        $this->minBounds = is_null($minBounds) ? null : $minBounds;
+        $this->minBounds = null === $minBounds ? null : $minBounds;
 
         return $this;
     }
 
-    /**
-     * @return int|null
-     */
     public function getMaxBounds(): ?int
     {
         return $this->maxBounds;
     }
 
-    /**
-     * @param int|null $maxBounds
-     *
-     * @return self
-     */
-    public function setMaxBounds(int $maxBounds = null): self
+    public function setMaxBounds(?int $maxBounds = null): self
     {
-        $this->maxBounds = is_null($maxBounds) ? null : $maxBounds;
+        $this->maxBounds = null === $maxBounds ? null : $maxBounds;
 
         return $this;
     }
 
-    /**
-     * @return string
-     */
     public function getCrossesAt(): string
     {
         return $this->crossesAt;
     }
 
-    /**
-     * @param string $value
-     *
-     * @return self
-     */
     public function setCrossesAt(string $value = self::CROSSES_AUTO): self
     {
         $this->crossesAt = $value;
@@ -277,19 +234,11 @@ public function setCrossesAt(string $value = self::CROSSES_AUTO): self
         return $this;
     }
 
-    /**
-     * @return bool
-     */
     public function isReversedOrder(): bool
     {
         return $this->isReversedOrder;
     }
 
-    /**
-     * @param bool $value
-     *
-     * @return self
-     */
     public function setIsReversedOrder(bool $value = false): self
     {
         $this->isReversedOrder = $value;
@@ -321,19 +270,11 @@ public function setMinorGridlines(Gridlines $minorGridlines): self
         return $this;
     }
 
-    /**
-     * @return string
-     */
     public function getMinorTickMark(): string
     {
         return $this->minorTickMark;
     }
 
-    /**
-     * @param string $tickMark
-     *
-     * @return self
-     */
     public function setMinorTickMark(string $tickMark = self::TICK_MARK_NONE): self
     {
         $this->minorTickMark = $tickMark;
@@ -341,19 +282,11 @@ public function setMinorTickMark(string $tickMark = self::TICK_MARK_NONE): self
         return $this;
     }
 
-    /**
-     * @return string
-     */
     public function getMajorTickMark(): string
     {
         return $this->majorTickMark;
     }
 
-    /**
-     * @param string $tickMark
-     *
-     * @return self
-     */
     public function setMajorTickMark(string $tickMark = self::TICK_MARK_NONE): self
     {
         $this->majorTickMark = $tickMark;
@@ -361,18 +294,13 @@ public function setMajorTickMark(string $tickMark = self::TICK_MARK_NONE): self
         return $this;
     }
 
-    /**
-     * @return float|null
-     */
     public function getMinorUnit(): ?float
     {
         return $this->minorUnit;
     }
 
     /**
-     * @param float|null $unit
-     *
-     * @return self
+     * @param null|float $unit
      */
     public function setMinorUnit($unit = null): self
     {
@@ -381,39 +309,23 @@ public function setMinorUnit($unit = null): self
         return $this;
     }
 
-    /**
-     * @return float|null
-     */
     public function getMajorUnit(): ?float
     {
         return $this->majorUnit;
     }
 
-    /**
-     * @param float|null $unit
-     *
-     * @return self
-     */
-    public function setMajorUnit(float $unit = null): self
+    public function setMajorUnit(?float $unit = null): self
     {
         $this->majorUnit = $unit;
 
         return $this;
     }
 
-    /**
-     * @return Outline
-     */
     public function getOutline(): Outline
     {
         return $this->outline;
     }
 
-    /**
-     * @param Outline $outline
-     *
-     * @return self
-     */
     public function setOutline(Outline $outline): self
     {
         $this->outline = $outline;
@@ -421,19 +333,11 @@ public function setOutline(Outline $outline): self
         return $this;
     }
 
-    /**
-     * @return int
-     */
     public function getTitleRotation(): int
     {
         return $this->titleRotation;
     }
 
-    /**
-     * @param int $titleRotation
-     *
-     * @return self
-     */
     public function setTitleRotation(int $titleRotation): self
     {
         if ($titleRotation < 0) {
@@ -448,7 +352,7 @@ public function setTitleRotation(int $titleRotation): self
     }
 
     /**
-     * Get hash code
+     * Get hash code.
      *
      * @return string Hash code
      */
@@ -470,7 +374,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
@@ -496,8 +400,6 @@ public function setHashIndex(int $value)
 
     /**
      * Axis is hidden ?
-     *
-     * @return bool
      */
     public function isVisible(): bool
     {
@@ -508,8 +410,6 @@ public function isVisible(): bool
      * Hide an axis.
      *
      * @param bool $value delete
-     *
-     * @return self
      */
     public function setIsVisible(bool $value): self
     {
@@ -518,19 +418,11 @@ public function setIsVisible(bool $value): self
         return $this;
     }
 
-    /**
-     * @return string
-     */
     public function getTickLabelPosition(): string
     {
         return $this->tickLabelPosition;
     }
 
-    /**
-     * @param string $value
-     *
-     * @return self
-     */
     public function setTickLabelPosition(string $value = self::TICK_LABEL_POSITION_NEXT_TO): self
     {
         if (in_array($value, [
diff --git a/src/PhpPresentation/Shape/Chart/Gridlines.php b/src/PhpPresentation/Shape/Chart/Gridlines.php
index 83f1248865..e1b78e6922 100644
--- a/src/PhpPresentation/Shape/Chart/Gridlines.php
+++ b/src/PhpPresentation/Shape/Chart/Gridlines.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Legend.php b/src/PhpPresentation/Shape/Chart/Legend.php
index 6878f62a8f..8798ea5553 100644
--- a/src/PhpPresentation/Shape/Chart/Legend.php
+++ b/src/PhpPresentation/Shape/Chart/Legend.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -83,7 +82,7 @@ class Legend implements ComparableInterface
     /**
      * Font.
      *
-     * @var Font|null
+     * @var null|Font
      */
     private $font;
 
@@ -250,9 +249,9 @@ public function getFont(): ?Font
     /**
      * Set font.
      *
-     * @param Font|null $pFont Font
+     * @param null|Font $pFont Font
      */
-    public function setFont(Font $pFont = null): self
+    public function setFont(?Font $pFont = null): self
     {
         $this->font = $pFont;
 
@@ -348,7 +347,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Shape/Chart/Marker.php b/src/PhpPresentation/Shape/Chart/Marker.php
index 008f787b3b..74d41d6550 100644
--- a/src/PhpPresentation/Shape/Chart/Marker.php
+++ b/src/PhpPresentation/Shape/Chart/Marker.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -102,19 +101,11 @@ public function setSize(int $size = 5): self
         return $this;
     }
 
-    /**
-     * @return Fill
-     */
     public function getFill(): Fill
     {
         return $this->fill;
     }
 
-    /**
-     * @param Fill $fill
-     *
-     * @return self
-     */
     public function setFill(Fill $fill): self
     {
         $this->fill = $fill;
@@ -122,19 +113,11 @@ public function setFill(Fill $fill): self
         return $this;
     }
 
-    /**
-     * @return Border
-     */
     public function getBorder(): Border
     {
         return $this->border;
     }
 
-    /**
-     * @param Border $border
-     *
-     * @return self
-     */
     public function setBorder(Border $border): self
     {
         $this->border = $border;
diff --git a/src/PhpPresentation/Shape/Chart/PlotArea.php b/src/PhpPresentation/Shape/Chart/PlotArea.php
index 2eb97174f8..ed5482493e 100644
--- a/src/PhpPresentation/Shape/Chart/PlotArea.php
+++ b/src/PhpPresentation/Shape/Chart/PlotArea.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -32,7 +31,7 @@ class PlotArea implements ComparableInterface
     /**
      * Type.
      *
-     * @var AbstractType|null
+     * @var null|AbstractType
      */
     private $type;
 
@@ -90,12 +89,9 @@ public function __clone()
         $this->axisY = clone $this->axisY;
     }
 
-    /**
-     * @throws UndefinedChartTypeException
-     */
     public function getType(): AbstractType
     {
-        if (is_null($this->type)) {
+        if (null === $this->type) {
             throw new UndefinedChartTypeException();
         }
 
@@ -208,7 +204,7 @@ public function setHeight(float $value = 0): self
      */
     public function getHashCode(): string
     {
-        return md5((is_null($this->type) ? 'null' : $this->type->getHashCode()) . $this->axisX->getHashCode() . $this->axisY->getHashCode() . $this->offsetX . $this->offsetY . $this->width . $this->height . __CLASS__);
+        return md5((null === $this->type ? 'null' : $this->type->getHashCode()) . $this->axisX->getHashCode() . $this->axisY->getHashCode() . $this->offsetX . $this->offsetY . $this->width . $this->height . __CLASS__);
     }
 
     /**
@@ -224,7 +220,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Shape/Chart/Series.php b/src/PhpPresentation/Shape/Chart/Series.php
index ea1bf49965..226521dabe 100644
--- a/src/PhpPresentation/Shape/Chart/Series.php
+++ b/src/PhpPresentation/Shape/Chart/Series.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -27,7 +26,7 @@
 
 class Series implements ComparableInterface
 {
-    /* Label positions */
+    // Label positions
     public const LABEL_BESTFIT = 'bestFit';
     public const LABEL_BOTTOM = 'b';
     public const LABEL_CENTER = 'ctr';
@@ -50,20 +49,20 @@ class Series implements ComparableInterface
      *
      * @var string
      */
-    protected $DlblNumFormat = '';
+    protected $dlblNumFormat = '';
 
     /**
-     * @var string|null
+     * @var null|string
      */
     protected $separator;
 
     /**
-     * @var Fill|null
+     * @var null|Fill
      */
     protected $fill;
 
     /**
-     * @var Font|null
+     * @var null|Font
      */
     protected $font;
 
@@ -78,7 +77,7 @@ class Series implements ComparableInterface
     protected $marker;
 
     /**
-     * @var Outline|null
+     * @var null|Outline
      */
     protected $outline;
 
@@ -134,7 +133,7 @@ class Series implements ComparableInterface
     /**
      * Values (key/value).
      *
-     * @var array<string, string|null>
+     * @var array<string, null|string>
      */
     private $values = [];
 
@@ -146,8 +145,7 @@ class Series implements ComparableInterface
     private $hashIndex;
 
     /**
-     * @param string $title
-     * @param array<string, string|null> $values
+     * @param array<string, null|string> $values
      */
     public function __construct(string $title = 'Series Title', array $values = [])
     {
@@ -184,7 +182,7 @@ public function setTitle(string $value = 'Series Title'): self
      */
     public function getDlblNumFormat(): string
     {
-        return $this->DlblNumFormat;
+        return $this->dlblNumFormat;
     }
 
     /**
@@ -192,7 +190,7 @@ public function getDlblNumFormat(): string
      */
     public function hasDlblNumFormat(): bool
     {
-        return !empty($this->DlblNumFormat);
+        return !empty($this->dlblNumFormat);
     }
 
     /**
@@ -200,7 +198,7 @@ public function hasDlblNumFormat(): bool
      */
     public function setDlblNumFormat(string $value = ''): self
     {
-        $this->DlblNumFormat = $value;
+        $this->dlblNumFormat = $value;
 
         return $this;
     }
@@ -213,7 +211,7 @@ public function getFill(): ?Fill
         return $this->fill;
     }
 
-    public function setFill(Fill $fill = null): self
+    public function setFill(?Fill $fill = null): self
     {
         $this->fill = $fill;
 
@@ -243,7 +241,7 @@ public function getDataPointFills(): array
     /**
      * Get Values.
      *
-     * @return array<string, string|null>
+     * @return array<string, null|string>
      */
     public function getValues(): array
     {
@@ -253,7 +251,7 @@ public function getValues(): array
     /**
      * Set Values.
      *
-     * @param array<string, string|null> $values
+     * @param array<string, null|string> $values
      */
     public function setValues(array $values = []): self
     {
@@ -264,11 +262,6 @@ public function setValues(array $values = []): self
 
     /**
      * Add Value.
-     *
-     * @param string $key
-     * @param string|null $value
-     *
-     * @return self
      */
     public function addValue(string $key, ?string $value): self
     {
@@ -369,7 +362,7 @@ public function setShowPercentage(bool $value): self
 
     public function hasShowSeparator(): bool
     {
-        return !is_null($this->separator);
+        return null !== $this->separator;
     }
 
     public function setSeparator(?string $pValue): self
@@ -419,9 +412,9 @@ public function getFont(): ?Font
     /**
      * Set font.
      *
-     * @param Font|null $pFont Font
+     * @param null|Font $pFont Font
      */
-    public function setFont(Font $pFont = null): self
+    public function setFont(?Font $pFont = null): self
     {
         $this->font = $pFont;
 
@@ -477,7 +470,7 @@ public function setOutline(?Outline $outline): self
      */
     public function getHashCode(): string
     {
-        return md5((is_null($this->fill) ? 'null' : $this->fill->getHashCode()) . (is_null($this->font) ? 'null' : $this->font->getHashCode()) . var_export($this->values, true) . var_export($this, true) . __CLASS__);
+        return md5((null === $this->fill ? 'null' : $this->fill->getHashCode()) . (null === $this->font ? 'null' : $this->font->getHashCode()) . var_export($this->values, true) . var_export($this, true) . __CLASS__);
     }
 
     /**
@@ -486,7 +479,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Shape/Chart/Title.php b/src/PhpPresentation/Shape/Chart/Title.php
index a03165724b..69494b7859 100644
--- a/src/PhpPresentation/Shape/Chart/Title.php
+++ b/src/PhpPresentation/Shape/Chart/Title.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -234,9 +233,9 @@ public function getFont(): ?Font
     /**
      * Set font.
      *
-     * @param Font|null $pFont Font
+     * @param null|Font $pFont Font
      */
-    public function setFont(Font $pFont = null): self
+    public function setFont(?Font $pFont = null): self
     {
         $this->font = $pFont;
 
@@ -281,7 +280,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Shape/Chart/Type/AbstractType.php b/src/PhpPresentation/Shape/Chart/Type/AbstractType.php
index 1121231157..b9bb21281c 100644
--- a/src/PhpPresentation/Shape/Chart/Type/AbstractType.php
+++ b/src/PhpPresentation/Shape/Chart/Type/AbstractType.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -76,7 +75,7 @@ public function hasAxisY(): bool
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Shape/Chart/Type/AbstractTypeBar.php b/src/PhpPresentation/Shape/Chart/Type/AbstractTypeBar.php
index 234717698d..6121195980 100644
--- a/src/PhpPresentation/Shape/Chart/Type/AbstractTypeBar.php
+++ b/src/PhpPresentation/Shape/Chart/Type/AbstractTypeBar.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -142,9 +141,6 @@ public function setGapWidthPercent($gapWidthPercent)
         return $this;
     }
 
-    /**
-     * @return int
-     */
     public function getOverlapWidthPercent(): int
     {
         return $this->overlapWidthPercent;
@@ -152,8 +148,6 @@ public function getOverlapWidthPercent(): int
 
     /**
      * @param int $value overlap width percentage
-     *
-     * @return self
      */
     public function setOverlapWidthPercent(int $value): self
     {
diff --git a/src/PhpPresentation/Shape/Chart/Type/AbstractTypeLine.php b/src/PhpPresentation/Shape/Chart/Type/AbstractTypeLine.php
index 3040f0bc3e..81b08bd054 100644
--- a/src/PhpPresentation/Shape/Chart/Type/AbstractTypeLine.php
+++ b/src/PhpPresentation/Shape/Chart/Type/AbstractTypeLine.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -31,8 +30,6 @@ class AbstractTypeLine extends AbstractType
 
     /**
      * Is Line Smooth?
-     *
-     * @return bool
      */
     public function isSmooth(): bool
     {
@@ -40,13 +37,9 @@ public function isSmooth(): bool
     }
 
     /**
-     * Set Line Smoothness
-     *
-     * @param bool $value
-     *
-     * @return AbstractTypeLine
+     * Set Line Smoothness.
      */
-    public function setIsSmooth(bool $value = true): AbstractTypeLine
+    public function setIsSmooth(bool $value = true): self
     {
         $this->isSmooth = $value;
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/AbstractTypePie.php b/src/PhpPresentation/Shape/Chart/Type/AbstractTypePie.php
index b538d9a16b..402d818ec0 100644
--- a/src/PhpPresentation/Shape/Chart/Type/AbstractTypePie.php
+++ b/src/PhpPresentation/Shape/Chart/Type/AbstractTypePie.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/Area.php b/src/PhpPresentation/Shape/Chart/Type/Area.php
index 49fc9bd6b2..bcdab02028 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Area.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Area.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/Bar.php b/src/PhpPresentation/Shape/Chart/Type/Bar.php
index 9ea5b3dc7e..e16787d902 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Bar.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Bar.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/Bar3D.php b/src/PhpPresentation/Shape/Chart/Type/Bar3D.php
index 1011ad071b..1e4fa0b865 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Bar3D.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Bar3D.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/Doughnut.php b/src/PhpPresentation/Shape/Chart/Type/Doughnut.php
index 292c823262..11cf586530 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Doughnut.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Doughnut.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/Line.php b/src/PhpPresentation/Shape/Chart/Type/Line.php
index cefca9dddc..b8d635e366 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Line.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Line.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/Pie.php b/src/PhpPresentation/Shape/Chart/Type/Pie.php
index 53cb6b1fe2..3cf6959c1b 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Pie.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Pie.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/Pie3D.php b/src/PhpPresentation/Shape/Chart/Type/Pie3D.php
index 05689c61ac..b8c63bec11 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Pie3D.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Pie3D.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/Type/Radar.php b/src/PhpPresentation/Shape/Chart/Type/Radar.php
index 9f45b5d5ef..322d30b4d0 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Radar.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Radar.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -25,7 +24,7 @@
 class Radar extends AbstractType implements ComparableInterface
 {
     /**
-     * Get hash code
+     * Get hash code.
      *
      * @return string Hash code
      */
diff --git a/src/PhpPresentation/Shape/Chart/Type/Scatter.php b/src/PhpPresentation/Shape/Chart/Type/Scatter.php
index 58f2576e7c..16668b34a7 100644
--- a/src/PhpPresentation/Shape/Chart/Type/Scatter.php
+++ b/src/PhpPresentation/Shape/Chart/Type/Scatter.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Chart/View3D.php b/src/PhpPresentation/Shape/Chart/View3D.php
index 21bbaeefe6..b6c0a49969 100644
--- a/src/PhpPresentation/Shape/Chart/View3D.php
+++ b/src/PhpPresentation/Shape/Chart/View3D.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -58,7 +57,7 @@ class View3D implements ComparableInterface
     /**
      * Height Percent.
      *
-     * @var int|null
+     * @var null|int
      */
     private $heightPercent = 100;
 
@@ -237,7 +236,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Shape/Comment.php b/src/PhpPresentation/Shape/Comment.php
index d909e05483..945faa879f 100644
--- a/src/PhpPresentation/Shape/Comment.php
+++ b/src/PhpPresentation/Shape/Comment.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -30,7 +29,7 @@
 class Comment extends AbstractShape implements ComparableInterface
 {
     /**
-     * @var Author|null
+     * @var null|Author
      */
     protected $author;
 
@@ -105,7 +104,7 @@ public function setText($text = '')
     /**
      * Comment has not height.
      *
-     * @return int|null
+     * @return null|int
      */
     public function getHeight()
     {
@@ -125,7 +124,7 @@ public function setHeight(int $pValue = 0)
     /**
      * Comment has not width.
      *
-     * @return int|null
+     * @return null|int
      */
     public function getWidth()
     {
diff --git a/src/PhpPresentation/Shape/Comment/Author.php b/src/PhpPresentation/Shape/Comment/Author.php
index 59784f3e94..be9e3a896c 100644
--- a/src/PhpPresentation/Shape/Comment/Author.php
+++ b/src/PhpPresentation/Shape/Comment/Author.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Drawing/AbstractDrawingAdapter.php b/src/PhpPresentation/Shape/Drawing/AbstractDrawingAdapter.php
index f361ba7d49..f06988cfe7 100644
--- a/src/PhpPresentation/Shape/Drawing/AbstractDrawingAdapter.php
+++ b/src/PhpPresentation/Shape/Drawing/AbstractDrawingAdapter.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Drawing/Base64.php b/src/PhpPresentation/Shape/Drawing/Base64.php
index 9d4dfbc905..5574c78e05 100644
--- a/src/PhpPresentation/Shape/Drawing/Base64.php
+++ b/src/PhpPresentation/Shape/Drawing/Base64.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -57,7 +56,7 @@ class Base64 extends AbstractDrawingAdapter
     public function __construct()
     {
         parent::__construct();
-        $this->uniqueName = md5(rand(0, 9999) . time() . rand(0, 9999));
+        $this->uniqueName = md5(mt_rand(0, 9999) . time() . mt_rand(0, 9999));
         $this->data = '';
     }
 
@@ -75,19 +74,16 @@ public function setData(string $data): self
 
     public function getContents(): string
     {
-        list(, $imageContents) = explode(';', $this->getData());
-        list(, $imageContents) = explode(',', $imageContents);
+        [, $imageContents] = explode(';', $this->getData());
+        [, $imageContents] = explode(',', $imageContents);
 
         return base64_decode($imageContents);
     }
 
-    /**
-     * @throws UnauthorizedMimetypeException
-     */
     public function getExtension(): string
     {
-        list($data) = explode(';', $this->getData());
-        list(, $mime) = explode(':', $data);
+        [$data] = explode(';', $this->getData());
+        [, $mime] = explode(':', $data);
 
         if (!array_key_exists($mime, $this->arrayMimeExtension)) {
             throw new UnauthorizedMimetypeException($mime, $this->arrayMimeExtension);
@@ -103,8 +99,8 @@ public function getIndexedFilename(): string
 
     public function getMimeType(): string
     {
-        list($data) = explode(';', $this->getData());
-        list(, $mime) = explode(':', $data);
+        [$data] = explode(';', $this->getData());
+        [, $mime] = explode(':', $data);
 
         if (!empty($mime)) {
             return $mime;
diff --git a/src/PhpPresentation/Shape/Drawing/File.php b/src/PhpPresentation/Shape/Drawing/File.php
index 754985a44c..9078c98a09 100644
--- a/src/PhpPresentation/Shape/Drawing/File.php
+++ b/src/PhpPresentation/Shape/Drawing/File.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -43,10 +42,6 @@ public function getPath(): string
      *
      * @param string $pValue File path
      * @param bool $pVerifyFile Verify file
-     *
-     * @throws FileNotFoundException
-     *
-     * @return self
      */
     public function setPath(string $pValue = '', bool $pVerifyFile = true): self
     {
@@ -59,7 +54,7 @@ public function setPath(string $pValue = '', bool $pVerifyFile = true): self
 
         if ($pVerifyFile) {
             if (0 == $this->width && 0 == $this->height) {
-                list($this->width, $this->height) = getimagesize($this->getPath());
+                [$this->width, $this->height] = getimagesize($this->getPath());
             }
         }
 
@@ -76,9 +71,6 @@ public function getExtension(): string
         return pathinfo($this->getPath(), PATHINFO_EXTENSION);
     }
 
-    /**
-     * @throws FileNotFoundException
-     */
     public function getMimeType(): string
     {
         if (!CommonFile::fileExists($this->getPath())) {
diff --git a/src/PhpPresentation/Shape/Drawing/Gd.php b/src/PhpPresentation/Shape/Drawing/Gd.php
index 59bcf8d3dd..16fa6fe165 100644
--- a/src/PhpPresentation/Shape/Drawing/Gd.php
+++ b/src/PhpPresentation/Shape/Drawing/Gd.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -22,13 +21,13 @@
 
 class Gd extends AbstractDrawingAdapter
 {
-    /* Rendering functions */
+    // Rendering functions
     public const RENDERING_DEFAULT = 'imagepng';
     public const RENDERING_PNG = 'imagepng';
     public const RENDERING_GIF = 'imagegif';
     public const RENDERING_JPEG = 'imagejpeg';
 
-    /* MIME types */
+    // MIME types
     public const MIMETYPE_DEFAULT = 'image/png';
     public const MIMETYPE_PNG = 'image/png';
     public const MIMETYPE_GIF = 'image/gif';
@@ -68,7 +67,7 @@ class Gd extends AbstractDrawingAdapter
     public function __construct()
     {
         parent::__construct();
-        $this->uniqueName = md5(rand(0, 9999) . time() . rand(0, 9999));
+        $this->uniqueName = md5(mt_rand(0, 9999) . time() . mt_rand(0, 9999));
     }
 
     /**
@@ -92,7 +91,7 @@ public function setImageResource($value = null)
     {
         $this->imageResource = $value;
 
-        if (!is_null($this->imageResource)) {
+        if (null !== $this->imageResource) {
             // Get width/height
             $this->width = imagesx($this->imageResource);
             $this->height = imagesy($this->imageResource);
diff --git a/src/PhpPresentation/Shape/Drawing/ZipFile.php b/src/PhpPresentation/Shape/Drawing/ZipFile.php
index 2a921e9d25..54c03a1666 100644
--- a/src/PhpPresentation/Shape/Drawing/ZipFile.php
+++ b/src/PhpPresentation/Shape/Drawing/ZipFile.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -22,6 +21,7 @@
 
 use PhpOffice\Common\File as CommonFile;
 use PhpOffice\PhpPresentation\Exception\FileNotFoundException;
+use ZipArchive;
 
 class ZipFile extends AbstractDrawingAdapter
 {
@@ -52,16 +52,13 @@ public function setPath(string $pValue = ''): self
         return $this;
     }
 
-    /**
-     * @throws FileNotFoundException
-     */
     public function getContents(): string
     {
         if (!CommonFile::fileExists($this->getZipFileOut())) {
             throw new FileNotFoundException($this->getZipFileOut());
         }
 
-        $imageZip = new \ZipArchive();
+        $imageZip = new ZipArchive();
         $imageZip->open($this->getZipFileOut());
         $imageContents = $imageZip->getFromName($this->getZipFileIn());
         $imageZip->close();
@@ -75,15 +72,12 @@ public function getExtension(): string
         return pathinfo($this->getZipFileIn(), PATHINFO_EXTENSION);
     }
 
-    /**
-     * @throws FileNotFoundException
-     */
     public function getMimeType(): string
     {
         if (!CommonFile::fileExists($this->getZipFileOut())) {
             throw new FileNotFoundException($this->getZipFileOut());
         }
-        $oArchive = new \ZipArchive();
+        $oArchive = new ZipArchive();
         $oArchive->open($this->getZipFileOut());
         if (!function_exists('getimagesizefromstring')) {
             $uri = 'data://application/octet-stream;base64,' . base64_encode($oArchive->getFromName($this->getZipFileIn()));
diff --git a/src/PhpPresentation/Shape/Group.php b/src/PhpPresentation/Shape/Group.php
index dcb29ac4e9..4945f15617 100644
--- a/src/PhpPresentation/Shape/Group.php
+++ b/src/PhpPresentation/Shape/Group.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -68,8 +67,6 @@ public function getShapeCollection()
 
     /**
      * Add shape to slide.
-     *
-     * @return AbstractShape
      */
     public function addShape(AbstractShape $shape): AbstractShape
     {
@@ -176,8 +173,6 @@ public function setHeight(int $pValue = 0)
 
     /**
      * Create rich text shape.
-     *
-     * @return RichText
      */
     public function createRichTextShape(): RichText
     {
@@ -194,8 +189,6 @@ public function createRichTextShape(): RichText
      * @param int $fromY Starting point y offset
      * @param int $toX Ending point x offset
      * @param int $toY Ending point y offset
-     *
-     * @return Line
      */
     public function createLineShape(int $fromX, int $fromY, int $toX, int $toY): Line
     {
@@ -207,8 +200,6 @@ public function createLineShape(int $fromX, int $fromY, int $toX, int $toY): Lin
 
     /**
      * Create chart shape.
-     *
-     * @return Chart
      */
     public function createChartShape(): Chart
     {
@@ -220,8 +211,6 @@ public function createChartShape(): Chart
 
     /**
      * Create drawing shape.
-     *
-     * @return Drawing\File
      */
     public function createDrawingShape(): Drawing\File
     {
@@ -235,8 +224,6 @@ public function createDrawingShape(): Drawing\File
      * Create table shape.
      *
      * @param int $columns Number of columns
-     *
-     * @return Table
      */
     public function createTableShape(int $columns = 1): Table
     {
diff --git a/src/PhpPresentation/Shape/Hyperlink.php b/src/PhpPresentation/Shape/Hyperlink.php
index 06e0be9ad7..97c0d2aec1 100644
--- a/src/PhpPresentation/Shape/Hyperlink.php
+++ b/src/PhpPresentation/Shape/Hyperlink.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -44,14 +43,14 @@ class Hyperlink
      *
      * @var int
      */
-    private $slideNumber = null;
+    private $slideNumber;
 
     /**
      * Slide relation ID (should not be used by user code!).
      *
      * @var string
      */
-    public $relationId = null;
+    public $relationId;
 
     /**
      * Hash index.
@@ -61,7 +60,7 @@ class Hyperlink
     private $hashIndex;
 
     /**
-     * If true, uses the text color, instead of theme color
+     * If true, uses the text color, instead of theme color.
      *
      * @var bool
      */
@@ -81,8 +80,6 @@ public function __construct(string $pUrl = '', string $pTooltip = '')
 
     /**
      * Get URL.
-     *
-     * @return string
      */
     public function getUrl(): string
     {
@@ -91,10 +88,6 @@ public function getUrl(): string
 
     /**
      * Set URL.
-     *
-     * @param string $value
-     *
-     * @return self
      */
     public function setUrl(string $value = ''): self
     {
@@ -105,8 +98,6 @@ public function setUrl(string $value = ''): self
 
     /**
      * Get tooltip.
-     *
-     * @return string
      */
     public function getTooltip(): string
     {
@@ -115,10 +106,6 @@ public function getTooltip(): string
 
     /**
      * Set tooltip.
-     *
-     * @param string $value
-     *
-     * @return self
      */
     public function setTooltip(string $value = ''): self
     {
@@ -129,8 +116,6 @@ public function setTooltip(string $value = ''): self
 
     /**
      * Get slide number.
-     *
-     * @return int
      */
     public function getSlideNumber(): int
     {
@@ -139,10 +124,6 @@ public function getSlideNumber(): int
 
     /**
      * Set slide number.
-     *
-     * @param int $value
-     *
-     * @return self
      */
     public function setSlideNumber(int $value = 1): self
     {
@@ -154,8 +135,6 @@ public function setSlideNumber(int $value = 1): self
 
     /**
      * Is this hyperlink internal? (to another slide).
-     *
-     * @return bool
      */
     public function isInternal(): bool
     {
@@ -178,7 +157,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
@@ -218,10 +197,6 @@ public function isTextColorUsed(): bool
      * Set whether or not to use text color for a hyperlink, instead of theme color.
      *
      * @see https://docs.microsoft.com/en-us/openspecs/office_standards/ms-odrawxml/014fbc20-3705-4812-b8cd-93f5af05b504
-     *
-     * @param bool $isTextColorUsed
-     *
-     * @return self
      */
     public function setIsTextColorUsed(bool $isTextColorUsed): self
     {
diff --git a/src/PhpPresentation/Shape/Line.php b/src/PhpPresentation/Shape/Line.php
index be7574d557..5e1c85aa57 100644
--- a/src/PhpPresentation/Shape/Line.php
+++ b/src/PhpPresentation/Shape/Line.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Media.php b/src/PhpPresentation/Shape/Media.php
index 1207195d57..b53cb86be4 100644
--- a/src/PhpPresentation/Shape/Media.php
+++ b/src/PhpPresentation/Shape/Media.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -33,12 +32,15 @@ public function getMimeType(): string
         switch (strtolower($this->getExtension())) {
             case 'mp4':
                 $mimetype = 'video/mp4';
+
                 break;
             case 'ogv':
                 $mimetype = 'video/ogg';
+
                 break;
             case 'wmv':
                 $mimetype = 'video/x-ms-wmv';
+
                 break;
             default:
                 $mimetype = 'application/octet-stream';
diff --git a/src/PhpPresentation/Shape/Placeholder.php b/src/PhpPresentation/Shape/Placeholder.php
index 45f6ac8202..1117736dcd 100644
--- a/src/PhpPresentation/Shape/Placeholder.php
+++ b/src/PhpPresentation/Shape/Placeholder.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -42,7 +41,7 @@ class Placeholder
      * Specifies the index of the placeholder. This is used when applying templates or changing layouts to
      * match a placeholder on one template or master to another.
      *
-     * @var int|null
+     * @var null|int
      */
     protected $idx;
 
diff --git a/src/PhpPresentation/Shape/RichText.php b/src/PhpPresentation/Shape/RichText.php
index b9082773ad..0e3403d52b 100644
--- a/src/PhpPresentation/Shape/RichText.php
+++ b/src/PhpPresentation/Shape/RichText.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -109,7 +108,7 @@ class RichText extends AbstractShape implements ComparableInterface
     private $columns = 1;
 
     /**
-     * The spacing between columns
+     * The spacing between columns.
      *
      * @var int
      */
@@ -146,28 +145,28 @@ class RichText extends AbstractShape implements ComparableInterface
     /**
      * Horizontal Auto Shrink.
      *
-     * @var bool|null
+     * @var null|bool
      */
     private $autoShrinkHorizontal;
 
     /**
      * Vertical Auto Shrink.
      *
-     * @var bool|null
+     * @var null|bool
      */
     private $autoShrinkVertical;
 
     /**
      * The percentage of the original font size to which the text is scaled.
      *
-     * @var float|null
+     * @var null|float
      */
     private $fontScale;
 
     /**
      * The percentage of the reduction of the line spacing.
      *
-     * @var float|null
+     * @var null|float
      */
     private $lnSpcReduction;
 
@@ -187,8 +186,6 @@ public function __construct()
 
     /**
      * Get active paragraph index.
-     *
-     * @return int
      */
     public function getActiveParagraphIndex(): int
     {
@@ -202,8 +199,6 @@ public function getActiveParagraph(): Paragraph
 
     /**
      * Set active paragraph.
-     *
-     * @throws OutOfBoundsException
      */
     public function setActiveParagraph(int $index = 0): Paragraph
     {
@@ -218,8 +213,6 @@ public function setActiveParagraph(int $index = 0): Paragraph
 
     /**
      * Get paragraph.
-     *
-     * @throws OutOfBoundsException
      */
     public function getParagraph(int $index = 0): Paragraph
     {
@@ -261,11 +254,9 @@ public function createParagraph(): Paragraph
     /**
      * Add text.
      *
-     * @param TextElementInterface|null $pText Rich text element
-     *
-     * @return self
+     * @param null|TextElementInterface $pText Rich text element
      */
-    public function addText(TextElementInterface $pText = null): self
+    public function addText(?TextElementInterface $pText = null): self
     {
         $this->richTextParagraphs[$this->activeParagraph]->addText($pText);
 
@@ -276,8 +267,6 @@ public function addText(TextElementInterface $pText = null): self
      * Create text (can not be formatted !).
      *
      * @param string $pText Text
-     *
-     * @return RichText\TextElement
      */
     public function createText(string $pText = ''): RichText\TextElement
     {
@@ -286,8 +275,6 @@ public function createText(string $pText = ''): RichText\TextElement
 
     /**
      * Create break.
-     *
-     * @return RichText\BreakElement
      */
     public function createBreak(): RichText\BreakElement
     {
@@ -298,8 +285,6 @@ public function createBreak(): RichText\BreakElement
      * Create text run (can be formatted).
      *
      * @param string $pText Text
-     *
-     * @return RichText\Run
      */
     public function createTextRun(string $pText = ''): RichText\Run
     {
@@ -308,8 +293,6 @@ public function createTextRun(string $pText = ''): RichText\Run
 
     /**
      * Get plain text.
-     *
-     * @return string
      */
     public function getPlainText(): string
     {
@@ -358,8 +341,6 @@ public function setParagraphs(array $paragraphs = []): self
 
     /**
      * Get text wrapping.
-     *
-     * @return string
      */
     public function getWrap(): string
     {
@@ -368,10 +349,6 @@ public function getWrap(): string
 
     /**
      * Set text wrapping.
-     *
-     * @param string $value
-     *
-     * @return self
      */
     public function setWrap(string $value = self::WRAP_SQUARE): self
     {
@@ -382,8 +359,6 @@ public function setWrap(string $value = self::WRAP_SQUARE): self
 
     /**
      * Get autofit.
-     *
-     * @return string
      */
     public function getAutoFit(): string
     {
@@ -408,22 +383,16 @@ public function getLineSpaceReduction(): ?float
 
     /**
      * Set autofit.
-     *
-     * @param string $value
-     * @param float|null $fontScale
-     * @param float|null $lnSpcReduction
-     *
-     * @return self
      */
-    public function setAutoFit(string $value = self::AUTOFIT_DEFAULT, float $fontScale = null, float $lnSpcReduction = null): self
+    public function setAutoFit(string $value = self::AUTOFIT_DEFAULT, ?float $fontScale = null, ?float $lnSpcReduction = null): self
     {
         $this->autoFit = $value;
 
-        if (!is_null($fontScale)) {
+        if (null !== $fontScale) {
             $this->fontScale = $fontScale;
         }
 
-        if (!is_null($lnSpcReduction)) {
+        if (null !== $lnSpcReduction) {
             $this->lnSpcReduction = $lnSpcReduction;
         }
 
@@ -432,8 +401,6 @@ public function setAutoFit(string $value = self::AUTOFIT_DEFAULT, float $fontSca
 
     /**
      * Get horizontal overflow.
-     *
-     * @return string
      */
     public function getHorizontalOverflow(): string
     {
@@ -442,10 +409,6 @@ public function getHorizontalOverflow(): string
 
     /**
      * Set horizontal overflow.
-     *
-     * @param string $value
-     *
-     * @return self
      */
     public function setHorizontalOverflow(string $value = self::OVERFLOW_OVERFLOW): self
     {
@@ -456,8 +419,6 @@ public function setHorizontalOverflow(string $value = self::OVERFLOW_OVERFLOW):
 
     /**
      * Get vertical overflow.
-     *
-     * @return string
      */
     public function getVerticalOverflow(): string
     {
@@ -466,10 +427,6 @@ public function getVerticalOverflow(): string
 
     /**
      * Set vertical overflow.
-     *
-     * @param string $value
-     *
-     * @return self
      */
     public function setVerticalOverflow(string $value = self::OVERFLOW_OVERFLOW): self
     {
@@ -480,8 +437,6 @@ public function setVerticalOverflow(string $value = self::OVERFLOW_OVERFLOW): se
 
     /**
      * Get upright.
-     *
-     * @return bool
      */
     public function isUpright(): bool
     {
@@ -490,10 +445,6 @@ public function isUpright(): bool
 
     /**
      * Set vertical.
-     *
-     * @param bool $value
-     *
-     * @return self
      */
     public function setUpright(bool $value = false): self
     {
@@ -504,8 +455,6 @@ public function setUpright(bool $value = false): self
 
     /**
      * Get vertical.
-     *
-     * @return bool
      */
     public function isVertical(): bool
     {
@@ -514,10 +463,6 @@ public function isVertical(): bool
 
     /**
      * Set vertical.
-     *
-     * @param bool $value
-     *
-     * @return self
      */
     public function setVertical(bool $value = false): self
     {
@@ -528,8 +473,6 @@ public function setVertical(bool $value = false): self
 
     /**
      * Get columns.
-     *
-     * @return int
      */
     public function getColumns(): int
     {
@@ -538,12 +481,6 @@ public function getColumns(): int
 
     /**
      * Set columns.
-     *
-     * @param int $value
-     *
-     * @return self
-     *
-     * @throws OutOfBoundsException
      */
     public function setColumns(int $value = 1): self
     {
@@ -558,8 +495,6 @@ public function setColumns(int $value = 1): self
 
     /**
      * Get bottom inset.
-     *
-     * @return float
      */
     public function getInsetBottom(): float
     {
@@ -568,10 +503,6 @@ public function getInsetBottom(): float
 
     /**
      * Set bottom inset.
-     *
-     * @param float $value
-     *
-     * @return self
      */
     public function setInsetBottom(float $value = 4.8): self
     {
@@ -582,8 +513,6 @@ public function setInsetBottom(float $value = 4.8): self
 
     /**
      * Get left inset.
-     *
-     * @return float
      */
     public function getInsetLeft(): float
     {
@@ -592,10 +521,6 @@ public function getInsetLeft(): float
 
     /**
      * Set left inset.
-     *
-     * @param float $value
-     *
-     * @return self
      */
     public function setInsetLeft(float $value = 9.6): self
     {
@@ -606,8 +531,6 @@ public function setInsetLeft(float $value = 9.6): self
 
     /**
      * Get right inset.
-     *
-     * @return float
      */
     public function getInsetRight(): float
     {
@@ -616,10 +539,6 @@ public function getInsetRight(): float
 
     /**
      * Set left inset.
-     *
-     * @param float $value
-     *
-     * @return self
      */
     public function setInsetRight(float $value = 9.6): self
     {
@@ -630,8 +549,6 @@ public function setInsetRight(float $value = 9.6): self
 
     /**
      * Get top inset.
-     *
-     * @return float
      */
     public function getInsetTop(): float
     {
@@ -640,10 +557,6 @@ public function getInsetTop(): float
 
     /**
      * Set top inset.
-     *
-     * @param float $value
-     *
-     * @return self
      */
     public function setInsetTop(float $value = 4.8): self
     {
@@ -652,7 +565,7 @@ public function setInsetTop(float $value = 4.8): self
         return $this;
     }
 
-    public function setAutoShrinkHorizontal(bool $value = null): self
+    public function setAutoShrinkHorizontal(?bool $value = null): self
     {
         $this->autoShrinkHorizontal = $value;
 
@@ -669,7 +582,7 @@ public function hasAutoShrinkHorizontal(): ?bool
      *
      * @return RichText
      */
-    public function setAutoShrinkVertical(bool $value = null): self
+    public function setAutoShrinkVertical(?bool $value = null): self
     {
         $this->autoShrinkVertical = $value;
 
@@ -685,9 +598,7 @@ public function hasAutoShrinkVertical(): ?bool
     }
 
     /**
-     * Get spacing between columns
-     *
-     * @return int
+     * Get spacing between columns.
      */
     public function getColumnSpacing(): int
     {
@@ -695,11 +606,7 @@ public function getColumnSpacing(): int
     }
 
     /**
-     * Set spacing between columns
-     *
-     * @param int $value
-     *
-     * @return self
+     * Set spacing between columns.
      */
     public function setColumnSpacing(int $value = 0): self
     {
diff --git a/src/PhpPresentation/Shape/RichText/BreakElement.php b/src/PhpPresentation/Shape/RichText/BreakElement.php
index 5df5f06486..093d4bb6de 100644
--- a/src/PhpPresentation/Shape/RichText/BreakElement.php
+++ b/src/PhpPresentation/Shape/RichText/BreakElement.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/RichText/Paragraph.php b/src/PhpPresentation/Shape/RichText/Paragraph.php
index 5fa26925cc..b1d80f8d24 100644
--- a/src/PhpPresentation/Shape/RichText/Paragraph.php
+++ b/src/PhpPresentation/Shape/RichText/Paragraph.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -50,7 +49,7 @@ class Paragraph implements ComparableInterface
     /**
      * Font.
      *
-     * @var Font|null
+     * @var null|Font
      */
     private $font;
 
@@ -127,9 +126,9 @@ public function getFont(): ?Font
     /**
      * Set font.
      *
-     * @param Font|null $pFont Font
+     * @param null|Font $pFont Font
      */
-    public function setFont(Font $pFont = null): self
+    public function setFont(?Font $pFont = null): self
     {
         $this->font = $pFont;
 
@@ -145,9 +144,9 @@ public function getBulletStyle(): ?Bullet
     }
 
     /**
-     * Set bullet style
+     * Set bullet style.
      */
-    public function setBulletStyle(Bullet $style = null): self
+    public function setBulletStyle(?Bullet $style = null): self
     {
         $this->bulletStyle = $style;
 
@@ -170,9 +169,9 @@ public function createText(string $pText = ''): TextElement
     /**
      * Add text.
      *
-     * @param TextElementInterface|null $pText Rich text element
+     * @param null|TextElementInterface $pText Rich text element
      */
-    public function addText(TextElementInterface $pText = null): self
+    public function addText(?TextElementInterface $pText = null): self
     {
         $this->richTextElements[] = $pText;
 
@@ -276,7 +275,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
@@ -300,20 +299,15 @@ public function setHashIndex(int $value)
         return $this;
     }
 
-    /**
-     * @return int
-     */
     public function getLineSpacing(): int
     {
         return $this->lineSpacing;
     }
 
     /**
-     * Value in points
+     * Value in points.
      *
      * @param int $lineSpacing
-     *
-     * @return self
      */
     public function setLineSpacing($lineSpacing): self
     {
@@ -322,19 +316,11 @@ public function setLineSpacing($lineSpacing): self
         return $this;
     }
 
-    /**
-     * @return string
-     */
     public function getLineSpacingMode(): string
     {
         return $this->lineSpacingMode;
     }
 
-    /**
-     * @param string $lineSpacingMode
-     *
-     * @return self
-     */
     public function setLineSpacingMode(string $lineSpacingMode): self
     {
         if (in_array($lineSpacingMode, [
@@ -348,9 +334,7 @@ public function setLineSpacingMode(string $lineSpacingMode): self
     }
 
     /**
-     * Value in points
-     *
-     * @return int
+     * Value in points.
      */
     public function getSpacingBefore(): int
     {
@@ -358,11 +342,7 @@ public function getSpacingBefore(): int
     }
 
     /**
-     * Value in points
-     *
-     * @param int $spacingBefore
-     *
-     * @return self
+     * Value in points.
      */
     public function setSpacingBefore(int $spacingBefore): self
     {
@@ -372,9 +352,7 @@ public function setSpacingBefore(int $spacingBefore): self
     }
 
     /**
-     * Value in points
-     *
-     * @return int
+     * Value in points.
      */
     public function getSpacingAfter(): int
     {
@@ -382,11 +360,7 @@ public function getSpacingAfter(): int
     }
 
     /**
-     * Value in points
-     *
-     * @param int $spacingAfter
-     *
-     * @return self
+     * Value in points.
      */
     public function setSpacingAfter(int $spacingAfter): self
     {
diff --git a/src/PhpPresentation/Shape/RichText/Run.php b/src/PhpPresentation/Shape/RichText/Run.php
index ba4f53250e..ba8fc12a5c 100644
--- a/src/PhpPresentation/Shape/RichText/Run.php
+++ b/src/PhpPresentation/Shape/RichText/Run.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -57,11 +56,11 @@ public function getFont(): Font
     /**
      * Set font.
      *
-     * @param Font|null $pFont Font
+     * @param null|Font $pFont Font
      *
      * @return \PhpOffice\PhpPresentation\Shape\RichText\TextElementInterface
      */
-    public function setFont(Font $pFont = null)
+    public function setFont(?Font $pFont = null)
     {
         $this->font = $pFont;
 
diff --git a/src/PhpPresentation/Shape/RichText/TextElement.php b/src/PhpPresentation/Shape/RichText/TextElement.php
index 3c74d02fd6..709860ffb2 100644
--- a/src/PhpPresentation/Shape/RichText/TextElement.php
+++ b/src/PhpPresentation/Shape/RichText/TextElement.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -43,7 +42,7 @@ class TextElement implements TextElementInterface
     /**
      * Hyperlink.
      *
-     * @var Hyperlink|null
+     * @var null|Hyperlink
      */
     protected $hyperlink;
 
@@ -92,12 +91,12 @@ public function getFont(): ?Font
 
     public function hasHyperlink(): bool
     {
-        return !is_null($this->hyperlink);
+        return null !== $this->hyperlink;
     }
 
     public function getHyperlink(): Hyperlink
     {
-        if (is_null($this->hyperlink)) {
+        if (null === $this->hyperlink) {
             $this->hyperlink = new Hyperlink();
         }
 
@@ -109,7 +108,7 @@ public function getHyperlink(): Hyperlink
      *
      * @return \PhpOffice\PhpPresentation\Shape\RichText\TextElement
      */
-    public function setHyperlink(Hyperlink $pHyperlink = null)
+    public function setHyperlink(?Hyperlink $pHyperlink = null)
     {
         $this->hyperlink = $pHyperlink;
 
@@ -147,6 +146,6 @@ public function setLanguage($language)
      */
     public function getHashCode(): string
     {
-        return md5($this->text . (is_null($this->hyperlink) ? '' : $this->hyperlink->getHashCode()) . __CLASS__);
+        return md5($this->text . (null === $this->hyperlink ? '' : $this->hyperlink->getHashCode()) . __CLASS__);
     }
 }
diff --git a/src/PhpPresentation/Shape/RichText/TextElementInterface.php b/src/PhpPresentation/Shape/RichText/TextElementInterface.php
index 4c704436cd..af2485bb0c 100644
--- a/src/PhpPresentation/Shape/RichText/TextElementInterface.php
+++ b/src/PhpPresentation/Shape/RichText/TextElementInterface.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Shape/Table.php b/src/PhpPresentation/Shape/Table.php
index d6313be119..496077877a 100644
--- a/src/PhpPresentation/Shape/Table.php
+++ b/src/PhpPresentation/Shape/Table.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -63,8 +62,6 @@ public function __construct($columns = 1)
      * Get row.
      *
      * @param int $row Row number
-     *
-     * @throws OutOfBoundsException
      */
     public function getRow(int $row = 0): Row
     {
@@ -79,11 +76,6 @@ public function getRow(int $row = 0): Row
         return $this->rows[$row];
     }
 
-    /**
-     * @param int $row
-     *
-     * @return bool
-     */
     public function hasRow(int $row): bool
     {
         return isset($this->rows[$row]);
@@ -101,8 +93,6 @@ public function getRows(): array
 
     /**
      * Create row.
-     *
-     * @return Row
      */
     public function createRow(): Row
     {
@@ -112,19 +102,11 @@ public function createRow(): Row
         return $row;
     }
 
-    /**
-     * @return int
-     */
     public function getNumColumns(): int
     {
         return $this->columnCount;
     }
 
-    /**
-     * @param int $numColumn
-     *
-     * @return self
-     */
     public function setNumColumns(int $numColumn): self
     {
         $this->columnCount = $numColumn;
diff --git a/src/PhpPresentation/Shape/Table/Cell.php b/src/PhpPresentation/Shape/Table/Cell.php
index c8e8a942c5..d750aa8ac8 100644
--- a/src/PhpPresentation/Shape/Table/Cell.php
+++ b/src/PhpPresentation/Shape/Table/Cell.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -128,8 +127,6 @@ public function getActiveParagraph(): Paragraph
      * Set active paragraph.
      *
      * @param int $index
-     *
-     * @throws OutOfBoundsException
      */
     public function setActiveParagraph($index = 0): Paragraph
     {
@@ -144,10 +141,6 @@ public function setActiveParagraph($index = 0): Paragraph
 
     /**
      * Get paragraph.
-     *
-     * @param int $index
-     *
-     * @throws OutOfBoundsException
      */
     public function getParagraph(int $index = 0): Paragraph
     {
@@ -187,7 +180,7 @@ public function createParagraph(): Paragraph
      *
      * @return \PhpOffice\PhpPresentation\Shape\Table\Cell
      */
-    public function addText(TextElementInterface $pText = null)
+    public function addText(?TextElementInterface $pText = null)
     {
         $this->richTextParagraphs[$this->activeParagraph]->addText($pText);
 
@@ -393,7 +386,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Shape/Table/Row.php b/src/PhpPresentation/Shape/Table/Row.php
index 039bbf16d0..59e9207e2e 100644
--- a/src/PhpPresentation/Shape/Table/Row.php
+++ b/src/PhpPresentation/Shape/Table/Row.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -81,8 +80,6 @@ public function __construct(int $columns = 1)
      * Get cell.
      *
      * @param int $cell Cell number
-     *
-     * @throws OutOfBoundsException
      */
     public function getCell(int $cell = 0): Cell
     {
@@ -101,8 +98,6 @@ public function getCell(int $cell = 0): Cell
      * Get cell.
      *
      * @param int $cell Cell number
-     *
-     * @return bool
      */
     public function hasCell(int $cell): bool
     {
@@ -121,10 +116,6 @@ public function getCells(): array
 
     /**
      * Next cell (moves one cell to the right).
-     *
-     * @return Cell
-     *
-     * @throws OutOfBoundsException
      */
     public function nextCell(): Cell
     {
@@ -144,8 +135,6 @@ public function nextCell(): Cell
 
     /**
      * Get fill.
-     *
-     * @return Fill
      */
     public function getFill(): Fill
     {
@@ -154,8 +143,6 @@ public function getFill(): Fill
 
     /**
      * Set fill.
-     *
-     * @return self
      */
     public function setFill(Fill $fill): self
     {
@@ -166,8 +153,6 @@ public function setFill(Fill $fill): self
 
     /**
      * Get height.
-     *
-     * @return int
      */
     public function getHeight(): int
     {
@@ -176,10 +161,6 @@ public function getHeight(): int
 
     /**
      * Set height.
-     *
-     * @param int $value
-     *
-     * @return self
      */
     public function setHeight(int $value = 0): self
     {
@@ -209,7 +190,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/ShapeContainerInterface.php b/src/PhpPresentation/ShapeContainerInterface.php
index 48e24f1674..a347c358ed 100644
--- a/src/PhpPresentation/ShapeContainerInterface.php
+++ b/src/PhpPresentation/ShapeContainerInterface.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Slide.php b/src/PhpPresentation/Slide.php
index 61c0d57757..7fbbea08b7 100644
--- a/src/PhpPresentation/Slide.php
+++ b/src/PhpPresentation/Slide.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -20,6 +19,7 @@
 
 namespace PhpOffice\PhpPresentation;
 
+use ArrayObject;
 use PhpOffice\PhpPresentation\Slide\AbstractSlide;
 use PhpOffice\PhpPresentation\Slide\Note;
 use PhpOffice\PhpPresentation\Slide\SlideLayout;
@@ -39,7 +39,7 @@ class Slide extends AbstractSlide implements ComparableInterface, ShapeContainer
     /**
      * Slide layout.
      *
-     * @var SlideLayout|null
+     * @var null|SlideLayout
      */
     private $slideLayout;
 
@@ -63,7 +63,7 @@ class Slide extends AbstractSlide implements ComparableInterface, ShapeContainer
     /**
      * Name of the title.
      *
-     * @var string|null
+     * @var null|string
      */
     protected $name;
 
@@ -72,14 +72,14 @@ class Slide extends AbstractSlide implements ComparableInterface, ShapeContainer
      *
      * @param PhpPresentation $pParent
      */
-    public function __construct(PhpPresentation $pParent = null)
+    public function __construct(?PhpPresentation $pParent = null)
     {
         // Set parent
         $this->parent = $pParent;
         // Shape collection
-        $this->shapeCollection = new \ArrayObject();
+        $this->shapeCollection = new ArrayObject();
         // Set identifier
-        $this->identifier = md5(rand(0, 9999) . time());
+        $this->identifier = md5(mt_rand(0, 9999) . time());
         // Set Slide Layout
         if ($this->parent instanceof PhpPresentation) {
             $arrayMasterSlides = $this->parent->getAllMasterSlides();
@@ -151,9 +151,9 @@ public function getNote(): Note
         return $this->slideNote;
     }
 
-    public function setNote(Note $note = null): self
+    public function setNote(?Note $note = null): self
     {
-        $this->slideNote = (is_null($note) ? new Note() : $note);
+        $this->slideNote = (null === $note ? new Note() : $note);
         $this->slideNote->setParent($this);
 
         return $this;
diff --git a/src/PhpPresentation/Slide/AbstractBackground.php b/src/PhpPresentation/Slide/AbstractBackground.php
index 42aa4d5856..94b9063b0a 100644
--- a/src/PhpPresentation/Slide/AbstractBackground.php
+++ b/src/PhpPresentation/Slide/AbstractBackground.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Slide/AbstractSlide.php b/src/PhpPresentation/Slide/AbstractSlide.php
index ad5acd19c4..b3d6fedfd6 100644
--- a/src/PhpPresentation/Slide/AbstractSlide.php
+++ b/src/PhpPresentation/Slide/AbstractSlide.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -39,8 +38,9 @@ abstract class AbstractSlide implements ComparableInterface, ShapeContainerInter
      * @var string
      */
     protected $relsIndex;
+
     /**
-     * @var Transition|null
+     * @var null|Transition
      */
     protected $slideTransition;
 
@@ -50,48 +50,56 @@ abstract class AbstractSlide implements ComparableInterface, ShapeContainerInter
      * @var array<int, AbstractShape>|ArrayObject<int, AbstractShape>
      */
     protected $shapeCollection = [];
+
     /**
      * Extent Y.
      *
      * @var int
      */
     protected $extentY;
+
     /**
      * Extent X.
      *
      * @var int
      */
     protected $extentX;
+
     /**
      * Offset X.
      *
      * @var int
      */
     protected $offsetX;
+
     /**
      * Offset Y.
      *
      * @var int
      */
     protected $offsetY;
+
     /**
      * Slide identifier.
      *
      * @var string
      */
     protected $identifier;
+
     /**
      * Hash index.
      *
      * @var int
      */
     protected $hashIndex;
+
     /**
      * Parent presentation.
      *
-     * @var PhpPresentation|null
+     * @var null|PhpPresentation
      */
     protected $parent;
+
     /**
      * Background of the slide.
      *
@@ -125,8 +133,6 @@ public function setShapeCollection($shapeCollection = [])
 
     /**
      * Add shape to slide.
-     *
-     * @return AbstractShape
      */
     public function addShape(AbstractShape $shape): AbstractShape
     {
@@ -207,7 +213,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
@@ -315,7 +321,7 @@ public function getParent(): ?PhpPresentation
     /**
      * Re-bind parent.
      */
-    public function rebindParent(PhpPresentation $parent): AbstractSlide
+    public function rebindParent(PhpPresentation $parent): self
     {
         $this->parent->removeSlideByIndex($this->parent->getIndex($this));
         $this->parent = $parent;
@@ -328,7 +334,7 @@ public function getBackground(): ?AbstractBackground
         return $this->background;
     }
 
-    public function setBackground(AbstractBackground $background = null): AbstractSlide
+    public function setBackground(?AbstractBackground $background = null): self
     {
         $this->background = $background;
 
@@ -340,7 +346,7 @@ public function getTransition(): ?Transition
         return $this->slideTransition;
     }
 
-    public function setTransition(Transition $transition = null): self
+    public function setTransition(?Transition $transition = null): self
     {
         $this->slideTransition = $transition;
 
diff --git a/src/PhpPresentation/Slide/Animation.php b/src/PhpPresentation/Slide/Animation.php
index 2e6d1dc48a..f5215ac2a1 100644
--- a/src/PhpPresentation/Slide/Animation.php
+++ b/src/PhpPresentation/Slide/Animation.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Slide/Background/Color.php b/src/PhpPresentation/Slide/Background/Color.php
index 24507d8dc4..22ed3e0632 100644
--- a/src/PhpPresentation/Slide/Background/Color.php
+++ b/src/PhpPresentation/Slide/Background/Color.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -26,11 +25,11 @@
 class Color extends AbstractBackground
 {
     /**
-     * @var StyleColor|null
+     * @var null|StyleColor
      */
     protected $color;
 
-    public function setColor(StyleColor $color = null): self
+    public function setColor(?StyleColor $color = null): self
     {
         $this->color = $color;
 
diff --git a/src/PhpPresentation/Slide/Background/Image.php b/src/PhpPresentation/Slide/Background/Image.php
index 39c998e2ba..eebd8aee7f 100644
--- a/src/PhpPresentation/Slide/Background/Image.php
+++ b/src/PhpPresentation/Slide/Background/Image.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -63,8 +62,6 @@ public function getPath(): ?string
      * @param string $pValue File path
      * @param bool $pVerifyFile Verify file
      *
-     * @throws FileNotFoundException
-     *
      * @return self
      */
     public function setPath(string $pValue = '', bool $pVerifyFile = true)
@@ -76,7 +73,7 @@ public function setPath(string $pValue = '', bool $pVerifyFile = true)
 
             if (0 == $this->width && 0 == $this->height) {
                 // Get width/height
-                list($this->width, $this->height) = getimagesize($pValue);
+                [$this->width, $this->height] = getimagesize($pValue);
             }
         }
         $this->path = $pValue;
@@ -86,8 +83,6 @@ public function setPath(string $pValue = '', bool $pVerifyFile = true)
 
     /**
      * Get Filename.
-     *
-     * @return string
      */
     public function getFilename(): string
     {
@@ -96,8 +91,6 @@ public function getFilename(): string
 
     /**
      * Get Extension.
-     *
-     * @return string
      */
     public function getExtension(): string
     {
diff --git a/src/PhpPresentation/Slide/Background/SchemeColor.php b/src/PhpPresentation/Slide/Background/SchemeColor.php
index 3cb785df53..380502e899 100644
--- a/src/PhpPresentation/Slide/Background/SchemeColor.php
+++ b/src/PhpPresentation/Slide/Background/SchemeColor.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -26,14 +25,14 @@
 class SchemeColor extends AbstractBackground
 {
     /**
-     * @var StyleSchemeColor|null
+     * @var null|StyleSchemeColor
      */
     protected $schemeColor;
 
     /**
      * @return $this
      */
-    public function setSchemeColor(StyleSchemeColor $color = null): self
+    public function setSchemeColor(?StyleSchemeColor $color = null): self
     {
         $this->schemeColor = $color;
 
diff --git a/src/PhpPresentation/Slide/Iterator.php b/src/PhpPresentation/Slide/Iterator.php
index d761be9a7d..6934b71f65 100644
--- a/src/PhpPresentation/Slide/Iterator.php
+++ b/src/PhpPresentation/Slide/Iterator.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -53,14 +52,14 @@ public function __construct(PhpPresentation $subject)
      */
     public function __destruct()
     {
-        unset($this->subject);
+        $this->subject = null;
     }
 
     /**
      * Rewind iterator.
      */
     #[\ReturnTypeWillChange]
-    public function rewind()
+    public function rewind(): void
     {
         $this->position = 0;
     }
@@ -70,6 +69,7 @@ public function rewind()
      *
      * @return \PhpOffice\PhpPresentation\Slide
      */
+    #[\ReturnTypeWillChange]
     public function current()
     {
         return $this->subject->getSlide($this->position);
@@ -80,6 +80,7 @@ public function current()
      *
      * @return int
      */
+    #[\ReturnTypeWillChange]
     public function key()
     {
         return $this->position;
@@ -89,7 +90,7 @@ public function key()
      * Next value.
      */
     #[\ReturnTypeWillChange]
-    public function next()
+    public function next(): void
     {
         ++$this->position;
     }
diff --git a/src/PhpPresentation/Slide/Layout.php b/src/PhpPresentation/Slide/Layout.php
index 1c1ec93cb6..e4c6726eec 100644
--- a/src/PhpPresentation/Slide/Layout.php
+++ b/src/PhpPresentation/Slide/Layout.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Slide/Note.php b/src/PhpPresentation/Slide/Note.php
index d1423a0262..587576062e 100644
--- a/src/PhpPresentation/Slide/Note.php
+++ b/src/PhpPresentation/Slide/Note.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -91,7 +90,7 @@ class Note implements ComparableInterface, ShapeContainerInterface
      *
      * @param Slide $pParent
      */
-    public function __construct(Slide $pParent = null)
+    public function __construct(?Slide $pParent = null)
     {
         // Set parent
         $this->parent = $pParent;
@@ -100,7 +99,7 @@ public function __construct(Slide $pParent = null)
         $this->shapeCollection = new ArrayObject();
 
         // Set identifier
-        $this->identifier = md5(rand(0, 9999) . time());
+        $this->identifier = md5(mt_rand(0, 9999) . time());
     }
 
     /**
@@ -115,8 +114,6 @@ public function getShapeCollection()
 
     /**
      * Add shape to slide.
-     *
-     * @return AbstractShape
      */
     public function addShape(AbstractShape $shape): AbstractShape
     {
@@ -230,7 +227,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Slide/SlideLayout.php b/src/PhpPresentation/Slide/SlideLayout.php
index 9c30db23ba..6393ca7e2c 100644
--- a/src/PhpPresentation/Slide/SlideLayout.php
+++ b/src/PhpPresentation/Slide/SlideLayout.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -20,6 +19,7 @@
 
 namespace PhpOffice\PhpPresentation\Slide;
 
+use ArrayObject;
 use PhpOffice\PhpPresentation\ComparableInterface;
 use PhpOffice\PhpPresentation\ShapeContainerInterface;
 use PhpOffice\PhpPresentation\Style\ColorMap;
@@ -30,30 +30,35 @@ class SlideLayout extends AbstractSlide implements ComparableInterface, ShapeCon
      * @var SlideMaster
      */
     protected $slideMaster;
+
     /**
      * Slide relation ID (should not be used by user code!).
      *
      * @var string
      */
     public $relationId;
+
     /**
      * Slide layout NR (should not be used by user code!).
      *
      * @var int
      */
     public $layoutNr;
+
     /**
      * Slide layout ID (should not be used by user code!).
      *
      * @var int
      */
     public $layoutId;
+
     /**
      * Slide layout ID (should not be used by user code!).
      *
-     * @var string|null
+     * @var null|string
      */
     protected $layoutName;
+
     /**
      * Mapping of colors to the theme.
      *
@@ -69,9 +74,9 @@ public function __construct(SlideMaster $pSlideMaster)
         // Set parent
         $this->slideMaster = $pSlideMaster;
         // Shape collection
-        $this->shapeCollection = new \ArrayObject();
+        $this->shapeCollection = new ArrayObject();
         // Set identifier
-        $this->identifier = md5(rand(0, 9999) . time());
+        $this->identifier = md5(mt_rand(0, 9999) . time());
         // Set a basic colorMap
         $this->colorMap = new ColorMap();
     }
diff --git a/src/PhpPresentation/Slide/SlideMaster.php b/src/PhpPresentation/Slide/SlideMaster.php
index 3966f008cf..9d877d3f2f 100644
--- a/src/PhpPresentation/Slide/SlideMaster.php
+++ b/src/PhpPresentation/Slide/SlideMaster.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -20,6 +19,7 @@
 
 namespace PhpOffice\PhpPresentation\Slide;
 
+use ArrayObject;
 use PhpOffice\PhpPresentation\ComparableInterface;
 use PhpOffice\PhpPresentation\PhpPresentation;
 use PhpOffice\PhpPresentation\ShapeContainerInterface;
@@ -37,20 +37,24 @@ class SlideMaster extends AbstractSlide implements ComparableInterface, ShapeCon
      * @var array<SlideLayout>
      */
     protected $slideLayouts = [];
+
     /**
      * Mapping of colors to the theme.
      *
      * @var ColorMap
      */
     public $colorMap;
+
     /**
      * @var TextStyle
      */
     protected $textStyles;
+
     /**
      * @var array<SchemeColor>
      */
     protected $arraySchemeColor = [];
+
     /**
      * @var array<string, string>
      */
@@ -72,14 +76,14 @@ class SlideMaster extends AbstractSlide implements ComparableInterface, ShapeCon
     /**
      * Create a new slideMaster.
      */
-    public function __construct(PhpPresentation $pParent = null)
+    public function __construct(?PhpPresentation $pParent = null)
     {
         // Set parent
         $this->parent = $pParent;
         // Shape collection
-        $this->shapeCollection = new \ArrayObject();
+        $this->shapeCollection = new ArrayObject();
         // Set identifier
-        $this->identifier = md5(rand(0, 9999) . time());
+        $this->identifier = md5(mt_rand(0, 9999) . time());
         // Set a basic colorMap
         $this->colorMap = new ColorMap();
         // Set a white background
@@ -98,8 +102,6 @@ public function __construct(PhpPresentation $pParent = null)
 
     /**
      * Create a slideLayout and add it to this presentation.
-     *
-     * @return SlideLayout
      */
     public function createSlideLayout(): SlideLayout
     {
@@ -111,12 +113,8 @@ public function createSlideLayout(): SlideLayout
 
     /**
      * Add slideLayout.
-     *
-     * @param SlideLayout|null $slideLayout
-     *
-     * @return SlideLayout
      */
-    public function addSlideLayout(SlideLayout $slideLayout = null): SlideLayout
+    public function addSlideLayout(?SlideLayout $slideLayout = null): SlideLayout
     {
         $this->slideLayouts[] = $slideLayout;
 
@@ -131,17 +129,11 @@ public function getAllSlideLayouts(): array
         return $this->slideLayouts;
     }
 
-    /**
-     * @return TextStyle
-     */
     public function getTextStyles(): TextStyle
     {
         return $this->textStyles;
     }
 
-    /**
-     * @return self
-     */
     public function setTextStyles(TextStyle $textStyle): self
     {
         $this->textStyles = $textStyle;
@@ -149,9 +141,6 @@ public function setTextStyles(TextStyle $textStyle): self
         return $this;
     }
 
-    /**
-     * @return self
-     */
     public function addSchemeColor(SchemeColor $schemeColor): self
     {
         $this->arraySchemeColor[$schemeColor->getValue()] = $schemeColor;
diff --git a/src/PhpPresentation/Slide/Transition.php b/src/PhpPresentation/Slide/Transition.php
index 9836f7c62e..b4589ba97e 100644
--- a/src/PhpPresentation/Slide/Transition.php
+++ b/src/PhpPresentation/Slide/Transition.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -81,22 +80,26 @@ class Transition
      * @var bool
      */
     protected $hasManualTrigger = false;
+
     /**
      * @var bool
      */
     protected $hasTimeTrigger = false;
+
     /**
-     * @var int|null
+     * @var null|int
      */
-    protected $advanceTimeTrigger = null;
+    protected $advanceTimeTrigger;
+
     /**
-     * @var string|null
+     * @var null|string
      */
-    protected $speed = null;
+    protected $speed;
+
     /**
-     * @var string|null
+     * @var null|string
      */
-    protected $transitionType = null;
+    protected $transitionType;
 
     public function setSpeed(?string $speed = self::SPEED_MEDIUM): self
     {
@@ -144,7 +147,7 @@ public function getAdvanceTimeTrigger(): ?int
         return $this->advanceTimeTrigger;
     }
 
-    public function setTransitionType(string $type = null): self
+    public function setTransitionType(?string $type = null): self
     {
         $this->transitionType = $type;
 
diff --git a/src/PhpPresentation/Style/Alignment.php b/src/PhpPresentation/Style/Alignment.php
index fae963ebe7..9e17e7dcdf 100644
--- a/src/PhpPresentation/Style/Alignment.php
+++ b/src/PhpPresentation/Style/Alignment.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -25,7 +24,7 @@
 
 class Alignment implements ComparableInterface
 {
-    /* Horizontal alignment */
+    // Horizontal alignment
     public const HORIZONTAL_GENERAL = 'l';
     public const HORIZONTAL_LEFT = 'l';
     public const HORIZONTAL_RIGHT = 'r';
@@ -33,14 +32,14 @@ class Alignment implements ComparableInterface
     public const HORIZONTAL_JUSTIFY = 'just';
     public const HORIZONTAL_DISTRIBUTED = 'dist';
 
-    /* Vertical alignment */
+    // Vertical alignment
     public const VERTICAL_BASE = 'base';
     public const VERTICAL_AUTO = 'auto';
     public const VERTICAL_BOTTOM = 'b';
     public const VERTICAL_TOP = 't';
     public const VERTICAL_CENTER = 'ctr';
 
-    /* Text direction */
+    // Text direction
     public const TEXT_DIRECTION_HORIZONTAL = 'horz';
     public const TEXT_DIRECTION_VERTICAL_90 = 'vert';
     public const TEXT_DIRECTION_VERTICAL_270 = 'vert270';
@@ -119,7 +118,7 @@ class Alignment implements ComparableInterface
     private $marginBottom = 0;
 
     /**
-     * RTL Direction Support
+     * RTL Direction Support.
      *
      * @var bool
      */
@@ -186,8 +185,6 @@ public function getLevel(): int
      * Set Level.
      *
      * @param int $pValue Ranging 0 - 8
-     *
-     * @throws OutOfBoundsException
      */
     public function setLevel(int $pValue = 0): self
     {
@@ -316,19 +313,11 @@ public function setTextDirection(string $pValue = self::TEXT_DIRECTION_HORIZONTA
         return $this;
     }
 
-    /**
-     * @return bool
-     */
     public function isRTL(): bool
     {
         return $this->isRTL;
     }
 
-    /**
-     * @param bool $value
-     *
-     * @return self
-     */
     public function setIsRTL(bool $value = false): self
     {
         $this->isRTL = $value;
@@ -361,7 +350,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Style/Border.php b/src/PhpPresentation/Style/Border.php
index 59b55ba3ad..e7bc865452 100644
--- a/src/PhpPresentation/Style/Border.php
+++ b/src/PhpPresentation/Style/Border.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -24,7 +23,7 @@
 
 class Border implements ComparableInterface
 {
-    /* Line style */
+    // Line style
     public const LINE_NONE = 'none';
     public const LINE_SINGLE = 'sng';
     public const LINE_DOUBLE = 'dbl';
@@ -32,7 +31,7 @@ class Border implements ComparableInterface
     public const LINE_THINTHICK = 'thinThick';
     public const LINE_TRI = 'tri';
 
-    /* Dash style */
+    // Dash style
     public const DASH_DASH = 'dash';
     public const DASH_DASHDOT = 'dashDot';
     public const DASH_DOT = 'dot';
@@ -87,8 +86,6 @@ public function __construct()
 
     /**
      * Get line width (in points).
-     *
-     * @return int
      */
     public function getLineWidth(): int
     {
@@ -97,10 +94,6 @@ public function getLineWidth(): int
 
     /**
      * Set line width (in points).
-     *
-     * @param int $pValue
-     *
-     * @return self
      */
     public function setLineWidth(int $pValue = 1): self
     {
@@ -111,8 +104,6 @@ public function setLineWidth(int $pValue = 1): self
 
     /**
      * Get line style.
-     *
-     * @return string
      */
     public function getLineStyle(): string
     {
@@ -121,10 +112,6 @@ public function getLineStyle(): string
 
     /**
      * Set line style.
-     *
-     * @param string $pValue
-     *
-     * @return self
      */
     public function setLineStyle(string $pValue = self::LINE_SINGLE): self
     {
@@ -138,8 +125,6 @@ public function setLineStyle(string $pValue = self::LINE_SINGLE): self
 
     /**
      * Get dash style.
-     *
-     * @return string
      */
     public function getDashStyle(): string
     {
@@ -148,10 +133,6 @@ public function getDashStyle(): string
 
     /**
      * Set dash style.
-     *
-     * @param string $pValue
-     *
-     * @return self
      */
     public function setDashStyle(string $pValue = self::DASH_SOLID): self
     {
@@ -175,12 +156,8 @@ public function getColor(): ?Color
 
     /**
      * Set Border Color.
-     *
-     * @param Color|null $color
-     *
-     * @return self
      */
-    public function setColor(Color $color = null): self
+    public function setColor(?Color $color = null): self
     {
         $this->color = $color;
 
@@ -209,7 +186,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Style/Borders.php b/src/PhpPresentation/Style/Borders.php
index 01fa0112ac..efdc2867ba 100644
--- a/src/PhpPresentation/Style/Borders.php
+++ b/src/PhpPresentation/Style/Borders.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -176,7 +175,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Style/Bullet.php b/src/PhpPresentation/Style/Bullet.php
index dd3729d5d7..e31a06c554 100644
--- a/src/PhpPresentation/Style/Bullet.php
+++ b/src/PhpPresentation/Style/Bullet.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -27,12 +26,12 @@
  */
 class Bullet implements ComparableInterface
 {
-    /* Bullet types */
+    // Bullet types
     public const TYPE_NONE = 'none';
     public const TYPE_BULLET = 'bullet';
     public const TYPE_NUMERIC = 'numeric';
 
-    /* Numeric bullet styles */
+    // Numeric bullet styles
     public const NUMERIC_DEFAULT = 'arabicPeriod';
     public const NUMERIC_ALPHALCPARENBOTH = 'alphaLcParenBoth';
     public const NUMERIC_ALPHAUCPARENBOTH = 'alphaUcParenBoth';
@@ -281,7 +280,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Style/Color.php b/src/PhpPresentation/Style/Color.php
index 56e51029f8..a10ffdc735 100644
--- a/src/PhpPresentation/Style/Color.php
+++ b/src/PhpPresentation/Style/Color.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -27,7 +26,7 @@
  */
 class Color implements ComparableInterface
 {
-    /* Colors */
+    // Colors
     public const COLOR_BLACK = 'FF000000';
     public const COLOR_WHITE = 'FFFFFFFF';
     public const COLOR_RED = 'FFFF0000';
@@ -94,8 +93,6 @@ public function setARGB($pValue = self::COLOR_BLACK)
     /**
      * Get the alpha % of the ARGB
      * Will return 100 if no ARGB.
-     *
-     * @return int
      */
     public function getAlpha(): int
     {
@@ -111,8 +108,6 @@ public function getAlpha(): int
     /**
      * Set the alpha % of the ARGB.
      *
-     * @param int $alpha
-     *
      * @return $this
      */
     public function setAlpha(int $alpha = 100): self
@@ -140,9 +135,9 @@ public function getRGB()
     {
         if (6 == strlen($this->argb)) {
             return $this->argb;
-        } else {
-            return substr($this->argb, 2);
         }
+
+        return substr($this->argb, 2);
     }
 
     /**
@@ -185,7 +180,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Style/ColorMap.php b/src/PhpPresentation/Style/ColorMap.php
index f95a3bc55b..5d67c4896a 100644
--- a/src/PhpPresentation/Style/ColorMap.php
+++ b/src/PhpPresentation/Style/ColorMap.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Style/Fill.php b/src/PhpPresentation/Style/Fill.php
index 19b92dbc2e..337ea3cb6b 100644
--- a/src/PhpPresentation/Style/Fill.php
+++ b/src/PhpPresentation/Style/Fill.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -24,7 +23,7 @@
 
 class Fill implements ComparableInterface
 {
-    /* Fill types */
+    // Fill types
     public const FILL_NONE = 'none';
     public const FILL_SOLID = 'solid';
     public const FILL_GRADIENT_LINEAR = 'linear';
@@ -93,8 +92,6 @@ public function __construct()
 
     /**
      * Get Fill Type.
-     *
-     * @return string
      */
     public function getFillType(): string
     {
@@ -105,8 +102,6 @@ public function getFillType(): string
      * Set Fill Type.
      *
      * @param string $pValue Fill type
-     *
-     * @return self
      */
     public function setFillType(string $pValue = self::FILL_NONE): self
     {
@@ -117,8 +112,6 @@ public function setFillType(string $pValue = self::FILL_NONE): self
 
     /**
      * Get Rotation.
-     *
-     * @return float
      */
     public function getRotation(): float
     {
@@ -127,10 +120,6 @@ public function getRotation(): float
 
     /**
      * Set Rotation.
-     *
-     * @param float $pValue
-     *
-     * @return self
      */
     public function setRotation(float $pValue = 0): self
     {
@@ -141,8 +130,6 @@ public function setRotation(float $pValue = 0): self
 
     /**
      * Get Start Color.
-     *
-     * @return Color
      */
     public function getStartColor(): Color
     {
@@ -153,10 +140,6 @@ public function getStartColor(): Color
 
     /**
      * Set Start Color.
-     *
-     * @param Color $pValue
-     *
-     * @return self
      */
     public function setStartColor(Color $pValue): self
     {
@@ -167,8 +150,6 @@ public function setStartColor(Color $pValue): self
 
     /**
      * Get End Color.
-     *
-     * @return Color
      */
     public function getEndColor(): Color
     {
@@ -179,10 +160,6 @@ public function getEndColor(): Color
 
     /**
      * Set End Color.
-     *
-     * @param Color $pValue
-     *
-     * @return self
      */
     public function setEndColor(Color $pValue): self
     {
@@ -213,7 +190,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Style/Font.php b/src/PhpPresentation/Style/Font.php
index 2e25b257a4..9010aa2734 100644
--- a/src/PhpPresentation/Style/Font.php
+++ b/src/PhpPresentation/Style/Font.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -27,7 +26,7 @@
  */
 class Font implements ComparableInterface
 {
-    /* Underline types */
+    // Underline types
     public const UNDERLINE_NONE = 'none';
     public const UNDERLINE_DASH = 'dash';
     public const UNDERLINE_DASHHEAVY = 'dashHeavy';
@@ -122,7 +121,7 @@ class Font implements ComparableInterface
     private $characterSpacing = 0;
 
     /**
-     * Format
+     * Format.
      *
      * @var string
      */
@@ -141,9 +140,7 @@ public function __construct()
     }
 
     /**
-     * Get Name
-     *
-     * @return string
+     * Get Name.
      */
     public function getName(): string
     {
@@ -151,11 +148,7 @@ public function getName(): string
     }
 
     /**
-     * Set Name
-     *
-     * @param string $pValue
-     *
-     * @return self
+     * Set Name.
      */
     public function setName(string $pValue = 'Calibri'): self
     {
@@ -169,8 +162,6 @@ public function setName(string $pValue = 'Calibri'): self
 
     /**
      * Get Character Spacing.
-     *
-     * @return float
      */
     public function getCharacterSpacing(): float
     {
@@ -180,10 +171,6 @@ public function getCharacterSpacing(): float
     /**
      * Set Character Spacing
      * Value in pt.
-     *
-     * @param float $pValue
-     *
-     * @return self
      */
     public function setCharacterSpacing(float $pValue = 0): self
     {
@@ -212,8 +199,6 @@ public function setSize(int $pValue = 10): self
 
     /**
      * Get Bold.
-     *
-     * @return bool
      */
     public function isBold(): bool
     {
@@ -232,8 +217,6 @@ public function setBold(bool $pValue = false): self
 
     /**
      * Get Italic.
-     *
-     * @return bool
      */
     public function isItalic(): bool
     {
@@ -252,8 +235,6 @@ public function setItalic(bool $pValue = false): self
 
     /**
      * Get SuperScript.
-     *
-     * @return bool
      */
     public function isSuperScript(): bool
     {
@@ -294,8 +275,6 @@ public function setSubScript(bool $pValue = false): self
 
     /**
      * Get Underline.
-     *
-     * @return string
      */
     public function getUnderline(): string
     {
@@ -306,8 +285,6 @@ public function getUnderline(): string
      * Set Underline.
      *
      * @param string $pValue Underline type
-     *
-     * @return self
      */
     public function setUnderline(string $pValue = self::UNDERLINE_NONE): self
     {
@@ -321,8 +298,6 @@ public function setUnderline(string $pValue = self::UNDERLINE_NONE): self
 
     /**
      * Get Strikethrough.
-     *
-     * @return bool
      */
     public function isStrikethrough(): bool
     {
@@ -358,9 +333,7 @@ public function setColor(Color $pValue): self
     }
 
     /**
-     * Get format
-     *
-     * @return string
+     * Get format.
      */
     public function getFormat(): string
     {
@@ -368,11 +341,7 @@ public function getFormat(): string
     }
 
     /**
-     * Set format
-     *
-     * @param string $value
-     *
-     * @return self
+     * Set format.
      */
     public function setFormat(string $value = self::FORMAT_LATIN): self
     {
@@ -415,7 +384,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Style/Outline.php b/src/PhpPresentation/Style/Outline.php
index 99714e27d6..ed7ba16563 100644
--- a/src/PhpPresentation/Style/Outline.php
+++ b/src/PhpPresentation/Style/Outline.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Style/SchemeColor.php b/src/PhpPresentation/Style/SchemeColor.php
index 040e103b13..04e7244256 100644
--- a/src/PhpPresentation/Style/SchemeColor.php
+++ b/src/PhpPresentation/Style/SchemeColor.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Style/Shadow.php b/src/PhpPresentation/Style/Shadow.php
index 826dd47d95..bdbae7e04a 100644
--- a/src/PhpPresentation/Style/Shadow.php
+++ b/src/PhpPresentation/Style/Shadow.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -27,7 +26,7 @@
  */
 class Shadow implements ComparableInterface
 {
-    /* Shadow alignment */
+    // Shadow alignment
     public const SHADOW_BOTTOM = 'b';
     public const SHADOW_BOTTOM_LEFT = 'bl';
     public const SHADOW_BOTTOM_RIGHT = 'br';
@@ -73,7 +72,7 @@ class Shadow implements ComparableInterface
     private $alignment = self::SHADOW_BOTTOM_RIGHT;
 
     /**
-     * @var Color|null
+     * @var null|Color
      */
     private $color;
 
@@ -200,7 +199,7 @@ public function getColor(): ?Color
     /**
      * Set Color.
      */
-    public function setColor(Color $pValue = null): self
+    public function setColor(?Color $pValue = null): self
     {
         $this->color = $pValue;
 
@@ -241,7 +240,7 @@ public function getHashCode(): string
      * Note that this index may vary during script execution! Only reliable moment is
      * while doing a write of a workbook and when changes are not allowed.
      *
-     * @return int|null Hash index
+     * @return null|int Hash index
      */
     public function getHashIndex(): ?int
     {
diff --git a/src/PhpPresentation/Style/TextStyle.php b/src/PhpPresentation/Style/TextStyle.php
index 64d7c5abf2..a57216e15d 100644
--- a/src/PhpPresentation/Style/TextStyle.php
+++ b/src/PhpPresentation/Style/TextStyle.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -28,10 +27,12 @@ class TextStyle
      * @var array<int, RichTextParagraph>
      */
     protected $bodyStyle = [];
+
     /**
      * @var array<int, RichTextParagraph>
      */
     protected $titleStyle = [];
+
     /**
      * @var array<int, RichTextParagraph>
      */
@@ -39,8 +40,6 @@ class TextStyle
 
     /**
      * TextStyle constructor.
-     *
-     * @param bool $default
      */
     public function __construct(bool $default = true)
     {
@@ -72,7 +71,7 @@ public function __construct(bool $default = true)
 
     private function checkLvl(?int $lvl): bool
     {
-        if (is_null($lvl) || $lvl > 9) {
+        if (null === $lvl || $lvl > 9) {
             return false;
         }
 
diff --git a/src/PhpPresentation/Writer/AbstractDecoratorWriter.php b/src/PhpPresentation/Writer/AbstractDecoratorWriter.php
index 9b12bf9364..aab1d0eda4 100644
--- a/src/PhpPresentation/Writer/AbstractDecoratorWriter.php
+++ b/src/PhpPresentation/Writer/AbstractDecoratorWriter.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -26,9 +25,6 @@
 
 abstract class AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     abstract public function render(): ZipInterface;
 
     /**
diff --git a/src/PhpPresentation/Writer/AbstractWriter.php b/src/PhpPresentation/Writer/AbstractWriter.php
index 14179efc39..3d935c4172 100644
--- a/src/PhpPresentation/Writer/AbstractWriter.php
+++ b/src/PhpPresentation/Writer/AbstractWriter.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -41,12 +40,12 @@ abstract class AbstractWriter
     /**
      * Private PhpPresentation.
      *
-     * @var PhpPresentation|null
+     * @var null|PhpPresentation
      */
     protected $oPresentation;
 
     /**
-     * @var ZipInterface|null
+     * @var null|ZipInterface
      */
     protected $oZipAdapter;
 
@@ -69,11 +68,11 @@ public function getPhpPresentation(): ?PhpPresentation
     /**
      * Get PhpPresentation object.
      *
-     * @param PhpPresentation|null $pPhpPresentation PhpPresentation object
+     * @param null|PhpPresentation $pPhpPresentation PhpPresentation object
      *
      * @return self
      */
-    public function setPhpPresentation(PhpPresentation $pPhpPresentation = null)
+    public function setPhpPresentation(?PhpPresentation $pPhpPresentation = null)
     {
         $this->oPresentation = $pPhpPresentation;
 
@@ -111,7 +110,7 @@ protected function allDrawings(): array
 
         // Get an array of all slide layouts
         $aSlideLayouts = [];
-        array_walk_recursive($aSlideMasterLayouts, function ($oSlideLayout) use (&$aSlideLayouts) {
+        array_walk_recursive($aSlideMasterLayouts, function ($oSlideLayout) use (&$aSlideLayouts): void {
             $aSlideLayouts[] = $oSlideLayout;
         });
 
diff --git a/src/PhpPresentation/Writer/ODPresentation.php b/src/PhpPresentation/Writer/ODPresentation.php
index a963259dbe..1e227dd9ca 100644
--- a/src/PhpPresentation/Writer/ODPresentation.php
+++ b/src/PhpPresentation/Writer/ODPresentation.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -28,6 +27,7 @@
 use PhpOffice\PhpPresentation\Exception\InvalidParameterException;
 use PhpOffice\PhpPresentation\HashTable;
 use PhpOffice\PhpPresentation\PhpPresentation;
+use ReflectionClass;
 
 /**
  * ODPresentation writer.
@@ -58,7 +58,7 @@ class ODPresentation extends AbstractWriter implements WriterInterface
      *
      * @param PhpPresentation $pPhpPresentation
      */
-    public function __construct(PhpPresentation $pPhpPresentation = null)
+    public function __construct(?PhpPresentation $pPhpPresentation = null)
     {
         // Assign PhpPresentation
         $this->setPhpPresentation($pPhpPresentation ?? new PhpPresentation());
@@ -74,10 +74,6 @@ public function __construct(PhpPresentation $pPhpPresentation = null)
 
     /**
      * Save PhpPresentation to file.
-     *
-     * @throws FileCopyException
-     * @throws FileRemoveException
-     * @throws InvalidParameterException
      */
     public function save(string $pFilename): void
     {
@@ -105,14 +101,14 @@ public function save(string $pFilename): void
         $arrayChart = [];
 
         $arrayFiles = [];
-        $oDir = new DirectoryIterator(dirname(__FILE__) . DIRECTORY_SEPARATOR . 'ODPresentation');
+        $oDir = new DirectoryIterator(__DIR__ . DIRECTORY_SEPARATOR . 'ODPresentation');
         foreach ($oDir as $oFile) {
             if (!$oFile->isFile()) {
                 continue;
             }
 
             $class = __NAMESPACE__ . '\\ODPresentation\\' . $oFile->getBasename('.php');
-            $class = new \ReflectionClass($class);
+            $class = new ReflectionClass($class);
 
             if ($class->isAbstract() || !$class->isSubclassOf('PhpOffice\PhpPresentation\Writer\ODPresentation\AbstractDecoratorWriter')) {
                 continue;
@@ -160,18 +156,15 @@ public function hasDiskCaching()
     /**
      * Set use disk caching where possible?
      *
-     * @param bool $pValue
      * @param string $directory Disk caching directory
      *
-     * @throws DirectoryNotFoundException
-     *
      * @return \PhpOffice\PhpPresentation\Writer\ODPresentation
      */
-    public function setUseDiskCaching(bool $pValue = false, string $directory = null)
+    public function setUseDiskCaching(bool $pValue = false, ?string $directory = null)
     {
         $this->useDiskCaching = $pValue;
 
-        if (!is_null($directory)) {
+        if (null !== $directory) {
             if (!is_dir($directory)) {
                 throw new DirectoryNotFoundException($directory);
             }
diff --git a/src/PhpPresentation/Writer/ODPresentation/AbstractDecoratorWriter.php b/src/PhpPresentation/Writer/ODPresentation/AbstractDecoratorWriter.php
index 7683106b67..98c6064ea9 100644
--- a/src/PhpPresentation/Writer/ODPresentation/AbstractDecoratorWriter.php
+++ b/src/PhpPresentation/Writer/ODPresentation/AbstractDecoratorWriter.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Writer/ODPresentation/Content.php b/src/PhpPresentation/Writer/ODPresentation/Content.php
index bf9fc5b655..4cd604b423 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Content.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Content.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -179,7 +178,7 @@ protected function writeContent(): string
                         $oAlign = $item['oAlign_' . $level];
                         // text:list-level-style-bullet
                         $objWriter->startElement('text:list-level-style-bullet');
-                        $objWriter->writeAttribute('text:level', intval($level) + 1);
+                        $objWriter->writeAttribute('text:level', (int) $level + 1);
                         $objWriter->writeAttribute('text:bullet-char', $oStyle->getBulletChar());
                         // style:list-level-properties
                         $objWriter->startElement('style:list-level-properties');
@@ -235,21 +234,27 @@ protected function writeContent(): string
                 switch ($item->getAlignment()->getHorizontal()) {
                     case Alignment::HORIZONTAL_LEFT:
                         $objWriter->writeAttribute('fo:text-align', 'left');
+
                         break;
                     case Alignment::HORIZONTAL_RIGHT:
                         $objWriter->writeAttribute('fo:text-align', 'right');
+
                         break;
                     case Alignment::HORIZONTAL_CENTER:
                         $objWriter->writeAttribute('fo:text-align', 'center');
+
                         break;
                     case Alignment::HORIZONTAL_JUSTIFY:
                         $objWriter->writeAttribute('fo:text-align', 'justify');
+
                         break;
                     case Alignment::HORIZONTAL_DISTRIBUTED:
                         $objWriter->writeAttribute('fo:text-align', 'justify');
+
                         break;
                     default:
                         $objWriter->writeAttribute('fo:text-align', 'left');
+
                         break;
                 }
                 $objWriter->writeAttribute(
@@ -278,6 +283,7 @@ protected function writeContent(): string
                         $objWriter->writeAttributeIf($item->getFont()->isBold(), 'fo:font-weight', 'bold');
                         $objWriter->writeAttribute('fo:language', ($item->getLanguage() ? $item->getLanguage() : 'en'));
                         $objWriter->writeAttribute('style:script-type', 'latin');
+
                         break;
                     case Font::FORMAT_EAST_ASIAN:
                         $objWriter->writeAttribute('style:font-family-asian', $item->getFont()->getName());
@@ -285,6 +291,7 @@ protected function writeContent(): string
                         $objWriter->writeAttributeIf($item->getFont()->isBold(), 'style:font-weight-asian', 'bold');
                         $objWriter->writeAttribute('style:language-asian', ($item->getLanguage() ? $item->getLanguage() : 'en'));
                         $objWriter->writeAttribute('style:script-type', 'asian');
+
                         break;
                     case Font::FORMAT_COMPLEX_SCRIPT:
                         $objWriter->writeAttribute('style:font-family-complex', $item->getFont()->getName());
@@ -292,6 +299,7 @@ protected function writeContent(): string
                         $objWriter->writeAttributeIf($item->getFont()->isBold(), 'style:font-weight-complex', 'bold');
                         $objWriter->writeAttribute('style:language-complex', ($item->getLanguage() ? $item->getLanguage() : 'en'));
                         $objWriter->writeAttribute('style:script-type', 'complex');
+
                         break;
                 }
 
@@ -318,7 +326,7 @@ protected function writeContent(): string
             $pSlide = $this->getPresentation()->getSlide($i);
             $objWriter->startElement('draw:page');
             $name = $pSlide->getName();
-            if (!is_null($name)) {
+            if (null !== $name) {
                 $objWriter->writeAttribute('draw:name', $name);
             }
             $objWriter->writeAttribute('draw:master-page-name', 'Standard');
@@ -549,7 +557,7 @@ protected function writeShapeTxt(XMLWriter $objWriter, RichText $shape): void
             } elseif ('bullet' == $paragraph->getBulletStyle()->getBulletType()) {
                 $bCstShpHasBullet = true;
                 // Open the bullet list
-                if ('bullet' != $sCstShpLastBullet || ($sCstShpLastBullet == $paragraph->getBulletStyle()->getBulletType() && $iCstShpLastBulletLvl < $paragraph->getAlignment()->getLevel())) {
+                if ('bullet' != $sCstShpLastBullet || $iCstShpLastBulletLvl < $paragraph->getAlignment()->getLevel()) {
                     // text:list
                     $objWriter->startElement('text:list');
                     $objWriter->writeAttribute('text:style-name', 'L_' . $paragraph->getBulletStyle()->getHashCode());
@@ -633,9 +641,7 @@ protected function writeShapeTxt(XMLWriter $objWriter, RichText $shape): void
      */
     protected function writeShapeComment(XMLWriter $objWriter, Comment $oShape): void
     {
-        /*
-         * Note : This element is not valid in the Schema 1.2
-         */
+        // Note : This element is not valid in the Schema 1.2
         // officeooo:annotation
         $objWriter->startElement('officeooo:annotation');
         $objWriter->writeAttribute('svg:x', number_format(CommonDrawing::pixelsToCentimeters((int) $oShape->getOffsetX()), 2, '.', '') . 'cm');
@@ -874,15 +880,18 @@ protected function writeTxtStyle(XMLWriter $objWriter, RichText $shape): void
             case Fill::FILL_GRADIENT_PATH:
                 $objWriter->writeAttribute('draw:fill', 'gradient');
                 $objWriter->writeAttribute('draw:fill-gradient-name', 'gradient_' . $shape->getFill()->getHashCode());
+
                 break;
             case Fill::FILL_SOLID:
                 $objWriter->writeAttribute('draw:fill', 'solid');
                 $objWriter->writeAttribute('draw:fill-color', '#' . $shape->getFill()->getStartColor()->getRGB());
+
                 break;
             case Fill::FILL_NONE:
             default:
                 $objWriter->writeAttribute('draw:fill', 'none');
                 $objWriter->writeAttribute('draw:fill-color', '#' . $shape->getFill()->getStartColor()->getRGB());
+
                 break;
         }
         // Border
@@ -894,6 +903,7 @@ protected function writeTxtStyle(XMLWriter $objWriter, RichText $shape): void
             switch ($shape->getBorder()->getDashStyle()) {
                 case Border::DASH_SOLID:
                     $objWriter->writeAttribute('draw:stroke', 'solid');
+
                     break;
                 case Border::DASH_DASH:
                 case Border::DASH_DASHDOT:
@@ -907,9 +917,11 @@ protected function writeTxtStyle(XMLWriter $objWriter, RichText $shape): void
                 case Border::DASH_SYSDOT:
                     $objWriter->writeAttribute('draw:stroke', 'dash');
                     $objWriter->writeAttribute('draw:stroke-dash', 'strokeDash_' . $shape->getBorder()->getDashStyle());
+
                     break;
                 default:
                     $objWriter->writeAttribute('draw:stroke', 'none');
+
                     break;
             }
         }
@@ -995,12 +1007,15 @@ protected function writeLineStyle(XMLWriter $objWriter, Line $shape): void
         switch ($shape->getBorder()->getLineStyle()) {
             case Border::LINE_NONE:
                 $objWriter->writeAttribute('draw:stroke', 'none');
+
                 break;
             case Border::LINE_SINGLE:
                 $objWriter->writeAttribute('draw:stroke', 'solid');
+
                 break;
             default:
                 $objWriter->writeAttribute('draw:stroke', 'none');
+
                 break;
         }
         $objWriter->writeAttribute('svg:stroke-color', '#' . $shape->getBorder()->getColor()->getRGB());
@@ -1034,9 +1049,7 @@ protected function writeTableStyle(XMLWriter $objWriter, Table $shape): void
                 $objWriter->writeAttribute('style:name', 'gr' . $this->shapeId . 'r' . $keyRow . 'c' . $keyCell);
                 $objWriter->writeAttribute('style:family', 'table-cell');
 
-                /*
-                 * Note : This element is not valid in the Schema 1.2
-                 */
+                // Note : This element is not valid in the Schema 1.2
                 // style:graphic-properties
                 if (Fill::FILL_NONE != $shapeCell->getFill()->getFillType()) {
                     $objWriter->startElement('style:graphic-properties');
@@ -1157,166 +1170,214 @@ protected function writeStyleSlide(XMLWriter $objWriter, Slide $slide, int $incP
         // style:style/style:drawing-page-properties
         $objWriter->startElement('style:drawing-page-properties');
         $objWriter->writeAttributeIf(!$slide->isVisible(), 'presentation:visibility', 'hidden');
-        if (!is_null($oTransition = $slide->getTransition())) {
+        if (null !== ($oTransition = $slide->getTransition())) {
             $objWriter->writeAttribute('presentation:duration', 'PT' . number_format($oTransition->getAdvanceTimeTrigger() / 1000, 6, '.', '') . 'S');
             $objWriter->writeAttributeIf($oTransition->hasManualTrigger(), 'presentation:transition-type', 'manual');
             $objWriter->writeAttributeIf($oTransition->hasTimeTrigger(), 'presentation:transition-type', 'automatic');
             switch ($oTransition->getSpeed()) {
                 case Transition::SPEED_FAST:
                     $objWriter->writeAttribute('presentation:transition-speed', 'fast');
+
                     break;
                 case Transition::SPEED_MEDIUM:
                     $objWriter->writeAttribute('presentation:transition-speed', 'medium');
+
                     break;
                 case Transition::SPEED_SLOW:
                     $objWriter->writeAttribute('presentation:transition-speed', 'slow');
+
                     break;
             }
 
-            /*
-             * http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#property-presentation_transition-style
-             */
+            // http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#property-presentation_transition-style
             switch ($oTransition->getTransitionType()) {
                 case Transition::TRANSITION_BLINDS_HORIZONTAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'horizontal-stripes');
+
                     break;
                 case Transition::TRANSITION_BLINDS_VERTICAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'vertical-stripes');
+
                     break;
                 case Transition::TRANSITION_CHECKER_HORIZONTAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'horizontal-checkerboard');
+
                     break;
                 case Transition::TRANSITION_CHECKER_VERTICAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'vertical-checkerboard');
+
                     break;
                 case Transition::TRANSITION_CIRCLE:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_COMB_HORIZONTAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_COMB_VERTICAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_COVER_DOWN:
                     $objWriter->writeAttribute('presentation:transition-style', 'uncover-to-bottom');
+
                     break;
                 case Transition::TRANSITION_COVER_LEFT:
                     $objWriter->writeAttribute('presentation:transition-style', 'uncover-to-left');
+
                     break;
                 case Transition::TRANSITION_COVER_LEFT_DOWN:
                     $objWriter->writeAttribute('presentation:transition-style', 'uncover-to-lowerleft');
+
                     break;
                 case Transition::TRANSITION_COVER_LEFT_UP:
                     $objWriter->writeAttribute('presentation:transition-style', 'uncover-to-upperleft');
+
                     break;
                 case Transition::TRANSITION_COVER_RIGHT:
                     $objWriter->writeAttribute('presentation:transition-style', 'uncover-to-right');
+
                     break;
                 case Transition::TRANSITION_COVER_RIGHT_DOWN:
                     $objWriter->writeAttribute('presentation:transition-style', 'uncover-to-lowerright');
+
                     break;
                 case Transition::TRANSITION_COVER_RIGHT_UP:
                     $objWriter->writeAttribute('presentation:transition-style', 'uncover-to-upperright');
+
                     break;
                 case Transition::TRANSITION_COVER_UP:
                     $objWriter->writeAttribute('presentation:transition-style', 'uncover-to-top');
+
                     break;
                 case Transition::TRANSITION_CUT:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_DIAMOND:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_DISSOLVE:
                     $objWriter->writeAttribute('presentation:transition-style', 'dissolve');
+
                     break;
                 case Transition::TRANSITION_FADE:
                     $objWriter->writeAttribute('presentation:transition-style', 'fade-from-center');
+
                     break;
                 case Transition::TRANSITION_NEWSFLASH:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_PLUS:
                     $objWriter->writeAttribute('presentation:transition-style', 'close');
+
                     break;
                 case Transition::TRANSITION_PULL_DOWN:
                     $objWriter->writeAttribute('presentation:transition-style', 'stretch-from-bottom');
+
                     break;
                 case Transition::TRANSITION_PULL_LEFT:
                     $objWriter->writeAttribute('presentation:transition-style', 'stretch-from-left');
+
                     break;
                 case Transition::TRANSITION_PULL_RIGHT:
                     $objWriter->writeAttribute('presentation:transition-style', 'stretch-from-right');
+
                     break;
                 case Transition::TRANSITION_PULL_UP:
                     $objWriter->writeAttribute('presentation:transition-style', 'stretch-from-top');
+
                     break;
                 case Transition::TRANSITION_PUSH_DOWN:
                     $objWriter->writeAttribute('presentation:transition-style', 'roll-from-bottom');
+
                     break;
                 case Transition::TRANSITION_PUSH_LEFT:
                     $objWriter->writeAttribute('presentation:transition-style', 'roll-from-left');
+
                     break;
                 case Transition::TRANSITION_PUSH_RIGHT:
                     $objWriter->writeAttribute('presentation:transition-style', 'roll-from-right');
+
                     break;
                 case Transition::TRANSITION_PUSH_UP:
                     $objWriter->writeAttribute('presentation:transition-style', 'roll-from-top');
+
                     break;
                 case Transition::TRANSITION_RANDOM:
                     $objWriter->writeAttribute('presentation:transition-style', 'random');
+
                     break;
                 case Transition::TRANSITION_RANDOMBAR_HORIZONTAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'horizontal-lines');
+
                     break;
                 case Transition::TRANSITION_RANDOMBAR_VERTICAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'vertical-lines');
+
                     break;
                 case Transition::TRANSITION_SPLIT_IN_HORIZONTAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'close-horizontal');
+
                     break;
                 case Transition::TRANSITION_SPLIT_OUT_HORIZONTAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'open-horizontal');
+
                     break;
                 case Transition::TRANSITION_SPLIT_IN_VERTICAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'close-vertical');
+
                     break;
                 case Transition::TRANSITION_SPLIT_OUT_VERTICAL:
                     $objWriter->writeAttribute('presentation:transition-style', 'open-vertical');
+
                     break;
                 case Transition::TRANSITION_STRIPS_LEFT_DOWN:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_STRIPS_LEFT_UP:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_STRIPS_RIGHT_DOWN:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_STRIPS_RIGHT_UP:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_WEDGE:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_WIPE_DOWN:
                     $objWriter->writeAttribute('presentation:transition-style', 'fade-from-bottom');
+
                     break;
                 case Transition::TRANSITION_WIPE_LEFT:
                     $objWriter->writeAttribute('presentation:transition-style', 'fade-from-left');
+
                     break;
                 case Transition::TRANSITION_WIPE_RIGHT:
                     $objWriter->writeAttribute('presentation:transition-style', 'fade-from-right');
+
                     break;
                 case Transition::TRANSITION_WIPE_UP:
                     $objWriter->writeAttribute('presentation:transition-style', 'fade-from-top');
+
                     break;
                 case Transition::TRANSITION_ZOOM_IN:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
                 case Transition::TRANSITION_ZOOM_OUT:
                     $objWriter->writeAttribute('presentation:transition-style', 'none');
+
                     break;
             }
         }
@@ -1347,10 +1408,12 @@ protected function writeStylePartFill(XMLWriter $objWriter, ?Fill $oFill): void
             case Fill::FILL_SOLID:
                 $objWriter->writeAttribute('draw:fill', 'solid');
                 $objWriter->writeAttribute('draw:fill-color', '#' . $oFill->getStartColor()->getRGB());
+
                 break;
             case Fill::FILL_NONE:
             default:
                 $objWriter->writeAttribute('draw:fill', 'none');
+
                 break;
         }
     }
diff --git a/src/PhpPresentation/Writer/ODPresentation/Meta.php b/src/PhpPresentation/Writer/ODPresentation/Meta.php
index d976503e8b..cc1ca03ab4 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Meta.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Meta.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -26,9 +25,6 @@
 
 class Meta extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         // Create XML writer
@@ -83,20 +79,24 @@ public function render(): ZipInterface
                 case DocumentProperties::PROPERTY_TYPE_FLOAT:
                     $objWriter->writeAttribute('meta:value-type', 'float');
                     $objWriter->writeRaw((string) $propertyValue);
+
                     break;
                 case DocumentProperties::PROPERTY_TYPE_BOOLEAN:
                     $objWriter->writeAttribute('meta:value-type', 'boolean');
                     $objWriter->writeRaw($propertyValue ? 'true' : 'false');
+
                     break;
                 case DocumentProperties::PROPERTY_TYPE_DATE:
                     $objWriter->writeAttribute('meta:value-type', 'date');
                     $objWriter->writeRaw(date(DATE_W3C, (int) $propertyValue));
+
                     break;
                 case DocumentProperties::PROPERTY_TYPE_STRING:
                 case DocumentProperties::PROPERTY_TYPE_UNKNOWN:
                 default:
                     $objWriter->writeAttribute('meta:value-type', 'string');
                     $objWriter->writeRaw((string) $propertyValue);
+
                     break;
             }
             $objWriter->endElement();
diff --git a/src/PhpPresentation/Writer/ODPresentation/MetaInfManifest.php b/src/PhpPresentation/Writer/ODPresentation/MetaInfManifest.php
index 49f023e763..b97f3d6f44 100644
--- a/src/PhpPresentation/Writer/ODPresentation/MetaInfManifest.php
+++ b/src/PhpPresentation/Writer/ODPresentation/MetaInfManifest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -27,9 +26,6 @@
 
 class MetaInfManifest extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         // Create XML writer
diff --git a/src/PhpPresentation/Writer/ODPresentation/Mimetype.php b/src/PhpPresentation/Writer/ODPresentation/Mimetype.php
index 80101241df..5a70604170 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Mimetype.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Mimetype.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -24,9 +23,6 @@
 
 class Mimetype extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         $this->getZip()->addFromString('mimetype', 'application/vnd.oasis.opendocument.presentation');
diff --git a/src/PhpPresentation/Writer/ODPresentation/ObjectsChart.php b/src/PhpPresentation/Writer/ODPresentation/ObjectsChart.php
index 12ded07239..41aa54b589 100644
--- a/src/PhpPresentation/Writer/ODPresentation/ObjectsChart.php
+++ b/src/PhpPresentation/Writer/ODPresentation/ObjectsChart.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -48,22 +47,27 @@ class ObjectsChart extends AbstractDecoratorWriter
      * @var XMLWriter
      */
     protected $xmlContent;
+
     /**
      * @var mixed
      */
     protected $arrayData;
+
     /**
      * @var mixed
      */
     protected $arrayTitle;
+
     /**
      * @var int
      */
     protected $numData;
+
     /**
      * @var int
      */
     protected $numSeries;
+
     /**
      * @var string
      */
@@ -326,15 +330,18 @@ protected function writeAxisMainStyle(Chart\Axis $axis, string $styleName, Abstr
         switch ($axis->getTickLabelPosition()) {
             case Axis::TICK_LABEL_POSITION_NEXT_TO:
                 $this->xmlContent->writeAttribute('chart:axis-label-position', 'near-axis');
+
                 break;
             case Axis::TICK_LABEL_POSITION_HIGH:
                 $this->xmlContent->writeAttribute('chart:axis-position', '0');
                 $this->xmlContent->writeAttribute('chart:axis-label-position', 'outside-end');
+
                 break;
             case Axis::TICK_LABEL_POSITION_LOW:
                 $this->xmlContent->writeAttribute('chart:axis-position', '0');
                 $this->xmlContent->writeAttribute('chart:axis-label-position', 'outside-start');
                 $this->xmlContent->writeAttribute('chart:tick-mark-position', 'at-axis');
+
                 break;
         }
         $this->xmlContent->writeAttributeIf($chartType instanceof Radar && $styleName == 'styleAxisX', 'chart:reverse-direction', 'true');
@@ -449,19 +456,24 @@ protected function writeLegend(Chart $chart): void
         switch ($chart->getLegend()->getPosition()) {
             case Chart\Legend::POSITION_BOTTOM:
                 $position = 'bottom';
+
                 break;
             case Chart\Legend::POSITION_LEFT:
                 $position = 'start';
+
                 break;
             case Chart\Legend::POSITION_TOP:
                 $position = 'top';
+
                 break;
             case Chart\Legend::POSITION_TOPRIGHT:
                 $position = 'top-end';
+
                 break;
             case Chart\Legend::POSITION_RIGHT:
             default:
                 $position = 'end';
+
                 break;
         }
         $this->xmlContent->writeAttribute('chart:legend-position', $position);
@@ -573,12 +585,15 @@ protected function writePlotAreaStyle(Chart $chart): void
         switch ($chart->getDisplayBlankAs()) {
             case Chart::BLANKAS_ZERO:
                 $this->xmlContent->writeAttribute('chart:treat-empty-cells', 'use-zero');
+
                 break;
             case Chart::BLANKAS_GAP:
                 $this->xmlContent->writeAttribute('chart:treat-empty-cells', 'leave-gap');
+
                 break;
             case Chart::BLANKAS_SPAN:
                 $this->xmlContent->writeAttribute('chart:treat-empty-cells', 'ignore');
+
                 break;
         }
         if ($chartType instanceof AbstractTypeBar) {
@@ -706,27 +721,27 @@ protected function writeSeriesStyle(Chart $chart, Chart\Series $series): void
         }
         if ($chartType instanceof Line || $chartType instanceof Scatter) {
             $oMarker = $series->getMarker();
-            /*
-             * @link : http://www.datypic.com/sc/odf/a-chart_symbol-type.html
-             */
+            // @link : http://www.datypic.com/sc/odf/a-chart_symbol-type.html
             $this->xmlContent->writeAttributeIf(Chart\Marker::SYMBOL_NONE == $oMarker->getSymbol(), 'chart:symbol-type', 'none');
-            /*
-             * @link : http://www.datypic.com/sc/odf/a-chart_symbol-name.html
-             */
+            // @link : http://www.datypic.com/sc/odf/a-chart_symbol-name.html
             $this->xmlContent->writeAttributeIf(Chart\Marker::SYMBOL_NONE != $oMarker->getSymbol(), 'chart:symbol-type', 'named-symbol');
             if (Chart\Marker::SYMBOL_NONE != $oMarker->getSymbol()) {
                 switch ($oMarker->getSymbol()) {
                     case Chart\Marker::SYMBOL_DASH:
                         $symbolName = 'horizontal-bar';
+
                         break;
                     case Chart\Marker::SYMBOL_DOT:
                         $symbolName = 'circle';
+
                         break;
                     case Chart\Marker::SYMBOL_TRIANGLE:
                         $symbolName = 'arrow-up';
+
                         break;
                     default:
                         $symbolName = $oMarker->getSymbol();
+
                         break;
                 }
                 $this->xmlContent->writeAttribute('chart:symbol-name', $symbolName);
@@ -880,13 +895,13 @@ protected function writeTable(): void
                     // table:table-cell
                     $this->xmlContent->startElement('table:table-cell');
 
-                    $cellValueTypeFloat = is_null($cell) ? true : is_numeric($cell);
+                    $cellValueTypeFloat = null === $cell ? true : is_numeric($cell);
                     $this->xmlContent->writeAttributeIf(!$cellValueTypeFloat, 'office:value-type', 'string');
                     $this->xmlContent->writeAttributeIf($cellValueTypeFloat, 'office:value-type', 'float');
-                    $this->xmlContent->writeAttributeIf($cellValueTypeFloat, 'office:value', is_null($cell) ? 'NaN' : $cell);
+                    $this->xmlContent->writeAttributeIf($cellValueTypeFloat, 'office:value', null === $cell ? 'NaN' : $cell);
                     // text:p
                     $this->xmlContent->startElement('text:p');
-                    $this->xmlContent->text(is_null($cell) ? 'NaN' : (string) $cell);
+                    $this->xmlContent->text(null === $cell ? 'NaN' : (string) $cell);
                     $this->xmlContent->endElement();
                     // > table:table-cell
                     $this->xmlContent->endElement();
diff --git a/src/PhpPresentation/Writer/ODPresentation/Pictures.php b/src/PhpPresentation/Writer/ODPresentation/Pictures.php
index ac8cfa9335..ba83e8306e 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Pictures.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Pictures.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -26,9 +25,6 @@
 
 class Pictures extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         $arrMedia = [];
diff --git a/src/PhpPresentation/Writer/ODPresentation/Styles.php b/src/PhpPresentation/Writer/ODPresentation/Styles.php
index 6bc8cbfb2a..a36a067cf9 100644
--- a/src/PhpPresentation/Writer/ODPresentation/Styles.php
+++ b/src/PhpPresentation/Writer/ODPresentation/Styles.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -39,6 +38,7 @@ class Styles extends AbstractDecoratorWriter
      * @var array<int, string>
      */
     protected $arrayGradient = [];
+
     /**
      * Stores font styles draw:stroke-dash nodes.
      *
@@ -199,6 +199,7 @@ protected function writeRichTextStyle(XMLWriter $objWriter, RichText $shape): vo
                         $objWriter->writeAttribute('draw:distance', '0.105cm');
                         $objWriter->writeAttribute('draw:dots2', '1');
                         $objWriter->writeAttribute('draw:dots2-length', '0.14cm');
+
                         break;
                     case Border::DASH_DASHDOT:
                         $objWriter->writeAttribute('draw:distance', '0.105cm');
@@ -206,16 +207,19 @@ protected function writeRichTextStyle(XMLWriter $objWriter, RichText $shape): vo
                         $objWriter->writeAttribute('draw:dots1-length', '0.035cm');
                         $objWriter->writeAttribute('draw:dots2', '1');
                         $objWriter->writeAttribute('draw:dots2-length', '0.14cm');
+
                         break;
                     case Border::DASH_DOT:
                         $objWriter->writeAttribute('draw:distance', '0.105cm');
                         $objWriter->writeAttribute('draw:dots1', '1');
                         $objWriter->writeAttribute('draw:dots1-length', '0.035cm');
+
                         break;
                     case Border::DASH_LARGEDASH:
                         $objWriter->writeAttribute('draw:distance', '0.105cm');
                         $objWriter->writeAttribute('draw:dots2', '1');
                         $objWriter->writeAttribute('draw:dots2-length', '0.28cm');
+
                         break;
                     case Border::DASH_LARGEDASHDOT:
                         $objWriter->writeAttribute('draw:distance', '0.105cm');
@@ -223,6 +227,7 @@ protected function writeRichTextStyle(XMLWriter $objWriter, RichText $shape): vo
                         $objWriter->writeAttribute('draw:dots1-length', '0.035cm');
                         $objWriter->writeAttribute('draw:dots2', '1');
                         $objWriter->writeAttribute('draw:dots2-length', '0.28cm');
+
                         break;
                     case Border::DASH_LARGEDASHDOTDOT:
                         $objWriter->writeAttribute('draw:distance', '0.105cm');
@@ -230,11 +235,13 @@ protected function writeRichTextStyle(XMLWriter $objWriter, RichText $shape): vo
                         $objWriter->writeAttribute('draw:dots1-length', '0.035cm');
                         $objWriter->writeAttribute('draw:dots2', '1');
                         $objWriter->writeAttribute('draw:dots2-length', '0.28cm');
+
                         break;
                     case Border::DASH_SYSDASH:
                         $objWriter->writeAttribute('draw:distance', '0.035cm');
                         $objWriter->writeAttribute('draw:dots2', '1');
                         $objWriter->writeAttribute('draw:dots2-length', '0.105cm');
+
                         break;
                     case Border::DASH_SYSDASHDOT:
                         $objWriter->writeAttribute('draw:distance', '0.035cm');
@@ -242,6 +249,7 @@ protected function writeRichTextStyle(XMLWriter $objWriter, RichText $shape): vo
                         $objWriter->writeAttribute('draw:dots1-length', '0.035cm');
                         $objWriter->writeAttribute('draw:dots2', '1');
                         $objWriter->writeAttribute('draw:dots2-length', '0.105cm');
+
                         break;
                     case Border::DASH_SYSDASHDOTDOT:
                         $objWriter->writeAttribute('draw:distance', '0.035cm');
@@ -249,11 +257,13 @@ protected function writeRichTextStyle(XMLWriter $objWriter, RichText $shape): vo
                         $objWriter->writeAttribute('draw:dots1-length', '0.035cm');
                         $objWriter->writeAttribute('draw:dots2', '1');
                         $objWriter->writeAttribute('draw:dots2-length', '0.105cm');
+
                         break;
                     case Border::DASH_SYSDOT:
                         $objWriter->writeAttribute('draw:distance', '0.035cm');
                         $objWriter->writeAttribute('draw:dots1', '1');
                         $objWriter->writeAttribute('draw:dots1-length', '0.035cm');
+
                         break;
                 }
                 $objWriter->endElement();
diff --git a/src/PhpPresentation/Writer/ODPresentation/ThumbnailsThumbnail.php b/src/PhpPresentation/Writer/ODPresentation/ThumbnailsThumbnail.php
index 1d754335f8..7d05129b66 100644
--- a/src/PhpPresentation/Writer/ODPresentation/ThumbnailsThumbnail.php
+++ b/src/PhpPresentation/Writer/ODPresentation/ThumbnailsThumbnail.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -32,7 +31,7 @@ public function render(): ZipInterface
             // PNG : 8bit, non-interlaced with full alpha transparency
             $gdImage = imagecreatefromstring(file_get_contents($pathThumbnail));
             if ($gdImage) {
-                list($width, $height) = getimagesize($pathThumbnail);
+                [$width, $height] = getimagesize($pathThumbnail);
 
                 $gdRender = imagecreatetruecolor(128, 128);
                 $colorBgAlpha = imagecolorallocatealpha($gdRender, 0, 0, 0, 127);
diff --git a/src/PhpPresentation/Writer/PowerPoint2007.php b/src/PhpPresentation/Writer/PowerPoint2007.php
index e98a61837b..934944a989 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -55,7 +54,7 @@ class PowerPoint2007 extends AbstractWriter implements WriterInterface
      *
      * @param PhpPresentation $pPhpPresentation
      */
-    public function __construct(PhpPresentation $pPhpPresentation = null)
+    public function __construct(?PhpPresentation $pPhpPresentation = null)
     {
         // Assign PhpPresentation
         $this->setPhpPresentation($pPhpPresentation ?? new PhpPresentation());
@@ -71,10 +70,6 @@ public function __construct(PhpPresentation $pPhpPresentation = null)
 
     /**
      * Save PhpPresentation to file.
-     *
-     * @throws FileCopyException
-     * @throws FileRemoveException
-     * @throws InvalidParameterException
      */
     public function save(string $pFilename): void
     {
@@ -98,7 +93,7 @@ public function save(string $pFilename): void
         $oZip = $this->getZipAdapter();
         $oZip->open($pFilename);
 
-        $oDir = new DirectoryIterator(dirname(__FILE__) . DIRECTORY_SEPARATOR . 'PowerPoint2007');
+        $oDir = new DirectoryIterator(__DIR__ . DIRECTORY_SEPARATOR . 'PowerPoint2007');
         $arrayFiles = [];
         foreach ($oDir as $oFile) {
             if (!$oFile->isFile()) {
@@ -152,18 +147,15 @@ public function hasDiskCaching()
     /**
      * Set use disk caching where possible?
      *
-     * @param bool $useDiskCaching
      * @param string $directory Disk caching directory
      *
-     * @throws DirectoryNotFoundException
-     *
      * @return \PhpOffice\PhpPresentation\Writer\PowerPoint2007
      */
-    public function setUseDiskCaching(bool $useDiskCaching = false, string $directory = null)
+    public function setUseDiskCaching(bool $useDiskCaching = false, ?string $directory = null)
     {
         $this->useDiskCaching = $useDiskCaching;
 
-        if (!is_null($directory)) {
+        if (null !== $directory) {
             if (!is_dir($directory)) {
                 throw new DirectoryNotFoundException($directory);
             }
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/AbstractDecoratorWriter.php b/src/PhpPresentation/Writer/PowerPoint2007/AbstractDecoratorWriter.php
index 362d941933..0c77e95164 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/AbstractDecoratorWriter.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/AbstractDecoratorWriter.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -59,7 +58,6 @@ protected function writeRelationship(XMLWriter $objWriter, int $pId, string $pTy
      * @param XMLWriter $objWriter XML Writer
      * @param Border $pBorder Border
      * @param string $pElementName Element name
-     * @param bool $isMarker
      */
     protected function writeBorder(XMLWriter $objWriter, Border $pBorder, string $pElementName = 'L', bool $isMarker = false): void
     {
@@ -125,7 +123,7 @@ protected function writeBorder(XMLWriter $objWriter, Border $pBorder, string $pE
 
     protected function writeColor(XMLWriter $objWriter, Color $color, ?int $alpha = null): void
     {
-        if (is_null($alpha)) {
+        if (null === $alpha) {
             $alpha = $color->getAlpha();
         }
 
@@ -145,7 +143,7 @@ protected function writeColor(XMLWriter $objWriter, Color $color, ?int $alpha =
      * Write Fill.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param Fill|null $pFill Fill style
+     * @param null|Fill $pFill Fill style
      */
     protected function writeFill(XMLWriter $objWriter, ?Fill $pFill): void
     {
@@ -257,7 +255,7 @@ protected function writePatternFill(XMLWriter $objWriter, Fill $pFill): void
     }
 
     /**
-     * Write Outline
+     * Write Outline.
      */
     protected function writeOutline(XMLWriter $objWriter, ?Outline $oOutline): void
     {
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/AbstractSlide.php b/src/PhpPresentation/Writer/PowerPoint2007/AbstractSlide.php
index c310379bd3..930a22959d 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/AbstractSlide.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/AbstractSlide.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -122,8 +121,6 @@ protected function writeDrawingRelations(AbstractSlideAlias $pSlideMaster, XMLWr
     /**
      * @param array<int, AbstractShape>|ArrayObject<int, AbstractShape> $shapes
      * @param int $shapeId
-     *
-     * @throws UndefinedChartTypeException
      */
     protected function writeShapeCollection(XMLWriter $objWriter, $shapes = [], &$shapeId = 0): void
     {
@@ -159,8 +156,6 @@ protected function writeShapeCollection(XMLWriter $objWriter, $shapes = [], &$sh
      * Write txt.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param RichText $shape
-     * @param int $shapeId
      */
     protected function writeShapeText(XMLWriter $objWriter, RichText $shape, int $shapeId): void
     {
@@ -191,7 +186,7 @@ protected function writeShapeText(XMLWriter $objWriter, RichText $shape, int $sh
             $objWriter->startElement('p:nvPr');
             $objWriter->startElement('p:ph');
             $objWriter->writeAttribute('type', $shape->getPlaceholder()->getType());
-            if (!is_null($shape->getPlaceholder()->getIdx())) {
+            if (null !== $shape->getPlaceholder()->getIdx()) {
                 $objWriter->writeAttribute('idx', $shape->getPlaceholder()->getIdx());
             }
             $objWriter->endElement();
@@ -272,10 +267,10 @@ protected function writeShapeText(XMLWriter $objWriter, RichText $shape, int $sh
             // a:spAutoFit
             $objWriter->startElement('a:' . $shape->getAutoFit());
             if (RichText::AUTOFIT_NORMAL == $shape->getAutoFit()) {
-                if (!is_null($shape->getFontScale())) {
+                if (null !== $shape->getFontScale()) {
                     $objWriter->writeAttribute('fontScale', $shape->getFontScale() * 1000);
                 }
-                if (!is_null($shape->getLineSpaceReduction())) {
+                if (null !== $shape->getLineSpaceReduction()) {
                     $objWriter->writeAttribute('lnSpcReduction', $shape->getLineSpaceReduction() * 1000);
                 }
             }
@@ -311,8 +306,6 @@ protected function writeShapeText(XMLWriter $objWriter, RichText $shape, int $sh
      * Write table.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param ShapeTable $shape
-     * @param int $shapeId
      */
     protected function writeShapeTable(XMLWriter $objWriter, ShapeTable $shape, int $shapeId): void
     {
@@ -1089,11 +1082,9 @@ protected function writeNote(Note $pNote): string
     }
 
     /**
-     * Write AutoShape
+     * Write AutoShape.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param AutoShape $shape
-     * @param int $shapeId
      */
     protected function writeShapeAutoShape(XMLWriter $objWriter, AutoShape $shape, int $shapeId): void
     {
@@ -1186,7 +1177,7 @@ protected function writeShapeAutoShape(XMLWriter $objWriter, AutoShape $shape, i
     }
 
     /**
-     * Write chart
+     * Write chart.
      *
      * @param XMLWriter $objWriter XML Writer
      */
@@ -1300,9 +1291,7 @@ protected function writeShapePic(XMLWriter $objWriter, AbstractGraphic $shape, i
             $objWriter->writeAttribute('type', $shape->getPlaceholder()->getType());
             $objWriter->endElement();
         }
-        /*
-         * @link : https://github.com/stefslon/exportToPPTX/blob/master/exportToPPTX.m#L2128
-         */
+        // @link : https://github.com/stefslon/exportToPPTX/blob/master/exportToPPTX.m#L2128
         if ($shape instanceof Media) {
             // p:nvPr > a:videoFile
             $objWriter->startElement('a:videoFile');
@@ -1514,9 +1503,7 @@ protected function writeSlideBackground(AbstractSlideAlias $pSlide, XMLWriter $o
             // > p:bgPr
             $objWriter->endElement();
         }
-        /*
-         * @link : http://www.officeopenxml.com/prSlide-background.php
-         */
+        // @link : http://www.officeopenxml.com/prSlide-background.php
         if ($oBackground instanceof Slide\Background\SchemeColor) {
             // p:bgRef
             $objWriter->startElement('p:bgRef');
@@ -1543,7 +1530,7 @@ protected function writeSlideTransition(XMLWriter $objWriter, ?Slide\Transition
             return;
         }
         $objWriter->startElement('p:transition');
-        if (!is_null($transition->getSpeed())) {
+        if (null !== $transition->getSpeed()) {
             $objWriter->writeAttribute('spd', $transition->getSpeed());
         }
         $objWriter->writeAttribute('advClick', $transition->hasManualTrigger() ? '1' : '0');
@@ -1556,222 +1543,269 @@ protected function writeSlideTransition(XMLWriter $objWriter, ?Slide\Transition
                 $objWriter->startElement('p:blinds');
                 $objWriter->writeAttribute('dir', 'horz');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_BLINDS_VERTICAL:
                 $objWriter->startElement('p:blinds');
                 $objWriter->writeAttribute('dir', 'vert');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_CHECKER_HORIZONTAL:
                 $objWriter->startElement('p:checker');
                 $objWriter->writeAttribute('dir', 'horz');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_CHECKER_VERTICAL:
                 $objWriter->startElement('p:checker');
                 $objWriter->writeAttribute('dir', 'vert');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_CIRCLE:
                 $objWriter->writeElement('p:circle');
+
                 break;
             case Slide\Transition::TRANSITION_COMB_HORIZONTAL:
                 $objWriter->startElement('p:comb');
                 $objWriter->writeAttribute('dir', 'horz');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COMB_VERTICAL:
                 $objWriter->startElement('p:comb');
                 $objWriter->writeAttribute('dir', 'vert');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COVER_DOWN:
                 $objWriter->startElement('p:cover');
                 $objWriter->writeAttribute('dir', 'd');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COVER_LEFT:
                 $objWriter->startElement('p:cover');
                 $objWriter->writeAttribute('dir', 'l');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COVER_LEFT_DOWN:
                 $objWriter->startElement('p:cover');
                 $objWriter->writeAttribute('dir', 'ld');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COVER_LEFT_UP:
                 $objWriter->startElement('p:cover');
                 $objWriter->writeAttribute('dir', 'lu');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COVER_RIGHT:
                 $objWriter->startElement('p:cover');
                 $objWriter->writeAttribute('dir', 'r');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COVER_RIGHT_DOWN:
                 $objWriter->startElement('p:cover');
                 $objWriter->writeAttribute('dir', 'rd');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COVER_RIGHT_UP:
                 $objWriter->startElement('p:cover');
                 $objWriter->writeAttribute('dir', 'ru');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_COVER_UP:
                 $objWriter->startElement('p:cover');
                 $objWriter->writeAttribute('dir', 'u');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_CUT:
                 $objWriter->writeElement('p:cut');
+
                 break;
             case Slide\Transition::TRANSITION_DIAMOND:
                 $objWriter->writeElement('p:diamond');
+
                 break;
             case Slide\Transition::TRANSITION_DISSOLVE:
                 $objWriter->writeElement('p:dissolve');
+
                 break;
             case Slide\Transition::TRANSITION_FADE:
                 $objWriter->writeElement('p:fade');
+
                 break;
             case Slide\Transition::TRANSITION_NEWSFLASH:
                 $objWriter->writeElement('p:newsflash');
+
                 break;
             case Slide\Transition::TRANSITION_PLUS:
                 $objWriter->writeElement('p:plus');
+
                 break;
             case Slide\Transition::TRANSITION_PULL_DOWN:
                 $objWriter->startElement('p:pull');
                 $objWriter->writeAttribute('dir', 'd');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_PULL_LEFT:
                 $objWriter->startElement('p:pull');
                 $objWriter->writeAttribute('dir', 'l');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_PULL_RIGHT:
                 $objWriter->startElement('p:pull');
                 $objWriter->writeAttribute('dir', 'r');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_PULL_UP:
                 $objWriter->startElement('p:pull');
                 $objWriter->writeAttribute('dir', 'u');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_PUSH_DOWN:
                 $objWriter->startElement('p:push');
                 $objWriter->writeAttribute('dir', 'd');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_PUSH_LEFT:
                 $objWriter->startElement('p:push');
                 $objWriter->writeAttribute('dir', 'l');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_PUSH_RIGHT:
                 $objWriter->startElement('p:push');
                 $objWriter->writeAttribute('dir', 'r');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_PUSH_UP:
                 $objWriter->startElement('p:push');
                 $objWriter->writeAttribute('dir', 'u');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_RANDOM:
                 $objWriter->writeElement('p:random');
+
                 break;
             case Slide\Transition::TRANSITION_RANDOMBAR_HORIZONTAL:
                 $objWriter->startElement('p:randomBar');
                 $objWriter->writeAttribute('dir', 'horz');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_RANDOMBAR_VERTICAL:
                 $objWriter->startElement('p:randomBar');
                 $objWriter->writeAttribute('dir', 'vert');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_SPLIT_IN_HORIZONTAL:
                 $objWriter->startElement('p:split');
                 $objWriter->writeAttribute('dir', 'in');
                 $objWriter->writeAttribute('orient', 'horz');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_SPLIT_OUT_HORIZONTAL:
                 $objWriter->startElement('p:split');
                 $objWriter->writeAttribute('dir', 'out');
                 $objWriter->writeAttribute('orient', 'horz');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_SPLIT_IN_VERTICAL:
                 $objWriter->startElement('p:split');
                 $objWriter->writeAttribute('dir', 'in');
                 $objWriter->writeAttribute('orient', 'vert');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_SPLIT_OUT_VERTICAL:
                 $objWriter->startElement('p:split');
                 $objWriter->writeAttribute('dir', 'out');
                 $objWriter->writeAttribute('orient', 'vert');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_STRIPS_LEFT_DOWN:
                 $objWriter->startElement('p:strips');
                 $objWriter->writeAttribute('dir', 'ld');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_STRIPS_LEFT_UP:
                 $objWriter->startElement('p:strips');
                 $objWriter->writeAttribute('dir', 'lu');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_STRIPS_RIGHT_DOWN:
                 $objWriter->startElement('p:strips');
                 $objWriter->writeAttribute('dir', 'rd');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_STRIPS_RIGHT_UP:
                 $objWriter->startElement('p:strips');
                 $objWriter->writeAttribute('dir', 'ru');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_WEDGE:
                 $objWriter->writeElement('p:wedge');
+
                 break;
             case Slide\Transition::TRANSITION_WIPE_DOWN:
                 $objWriter->startElement('p:wipe');
                 $objWriter->writeAttribute('dir', 'd');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_WIPE_LEFT:
                 $objWriter->startElement('p:wipe');
                 $objWriter->writeAttribute('dir', 'l');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_WIPE_RIGHT:
                 $objWriter->startElement('p:wipe');
                 $objWriter->writeAttribute('dir', 'r');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_WIPE_UP:
                 $objWriter->startElement('p:wipe');
                 $objWriter->writeAttribute('dir', 'u');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_ZOOM_IN:
                 $objWriter->startElement('p:zoom');
                 $objWriter->writeAttribute('dir', 'in');
                 $objWriter->endElement();
+
                 break;
             case Slide\Transition::TRANSITION_ZOOM_OUT:
                 $objWriter->startElement('p:zoom');
                 $objWriter->writeAttribute('dir', 'out');
                 $objWriter->endElement();
+
                 break;
         }
 
@@ -1782,10 +1816,10 @@ private function getGUID(): string
     {
         if (function_exists('com_create_guid')) {
             return com_create_guid();
-        } else {
-            mt_srand(intval(microtime(true) * 10000));
-            $charid = strtoupper(md5(uniqid((string) rand(), true)));
-            $hyphen = chr(45); // "-"
+        }
+        mt_srand((int) (microtime(true) * 10000));
+        $charid = strtoupper(md5(uniqid((string) mt_rand(), true)));
+        $hyphen = chr(45); // "-"
             $uuid = chr(123)// "{"
                 . substr($charid, 0, 8) . $hyphen
                 . substr($charid, 8, 4) . $hyphen
@@ -1794,7 +1828,6 @@ private function getGUID(): string
                 . substr($charid, 20, 12)
                 . chr(125); // "}"
 
-            return $uuid;
-        }
+        return $uuid;
     }
 }
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/CommentAuthors.php b/src/PhpPresentation/Writer/PowerPoint2007/CommentAuthors.php
index 35b90e1774..a73a88518c 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/CommentAuthors.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/CommentAuthors.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/ContentTypes.php b/src/PhpPresentation/Writer/PowerPoint2007/ContentTypes.php
index 6d0a6d7e34..541e8c1d14 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/ContentTypes.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/ContentTypes.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -93,6 +92,7 @@ public function render(): ZipInterface
                 if ($oShape instanceof Comment) {
                     $this->writeOverrideContentType($objWriter, '/ppt/comments/comment' . ($i + 1) . '.xml', 'application/vnd.openxmlformats-officedocument.presentationml.comments+xml');
                     $hasComments = true;
+
                     break;
                 }
             }
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsApp.php b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsApp.php
index fe81c5086c..882cf3c8cf 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsApp.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsApp.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCore.php b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCore.php
index f1afb28df9..63897ee18e 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCore.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCore.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -50,13 +49,13 @@ public function render(): ZipInterface
         // dcterms:created
         $objWriter->startElement('dcterms:created');
         $objWriter->writeAttribute('xsi:type', 'dcterms:W3CDTF');
-        $objWriter->writeRaw(gmdate("Y-m-d\TH:i:s\Z", $this->oPresentation->getDocumentProperties()->getCreated()));
+        $objWriter->writeRaw(gmdate('Y-m-d\\TH:i:s\\Z', $this->oPresentation->getDocumentProperties()->getCreated()));
         $objWriter->endElement();
 
         // dcterms:modified
         $objWriter->startElement('dcterms:modified');
         $objWriter->writeAttribute('xsi:type', 'dcterms:W3CDTF');
-        $objWriter->writeRaw(gmdate("Y-m-d\TH:i:s\Z", $this->oPresentation->getDocumentProperties()->getModified()));
+        $objWriter->writeRaw(gmdate('Y-m-d\\TH:i:s\\Z', $this->oPresentation->getDocumentProperties()->getModified()));
         $objWriter->endElement();
 
         // dc:title
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCustom.php b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCustom.php
index ea651ac402..ccb257fa43 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCustom.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsCustom.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -68,20 +67,25 @@ public function render(): ZipInterface
             switch ($propertyType) {
                 case DocumentProperties::PROPERTY_TYPE_INTEGER:
                     $objWriter->writeElement('vt:i4', (string) $propertyValue);
+
                     break;
                 case DocumentProperties::PROPERTY_TYPE_FLOAT:
                     $objWriter->writeElement('vt:r8', (string) $propertyValue);
+
                     break;
                 case DocumentProperties::PROPERTY_TYPE_BOOLEAN:
                     $objWriter->writeElement('vt:bool', $propertyValue ? 'true' : 'false');
+
                     break;
                 case DocumentProperties::PROPERTY_TYPE_DATE:
                     $objWriter->startElement('vt:filetime');
                     $objWriter->writeRaw(date(DATE_W3C, (int) $propertyValue));
                     $objWriter->endElement();
+
                     break;
                 default:
                     $objWriter->writeElement('vt:lpwstr', (string) $propertyValue);
+
                     break;
             }
             $objWriter->endElement();
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsThumbnail.php b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsThumbnail.php
index 6c54be1ecf..358affd6a4 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/DocPropsThumbnail.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/DocPropsThumbnail.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptCharts.php b/src/PhpPresentation/Writer/PowerPoint2007/PptCharts.php
index 4d03776f14..5076aa8493 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptCharts.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptCharts.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -48,9 +47,6 @@
 
 class PptCharts extends AbstractDecoratorWriter
 {
-    /**
-     * @throws FileRemoveException
-     */
     public function render(): ZipInterface
     {
         for ($i = 0; $i < $this->getDrawingHashTable()->count(); ++$i) {
@@ -229,8 +225,6 @@ protected function writeChart(Chart $chart): string
      * Write chart to XML format.
      *
      * @return string String output
-     *
-     * @throws FileRemoveException
      */
     protected function writeSpreadsheet(PhpPresentation $presentation, Chart $chart, string $tempName): string
     {
@@ -244,7 +238,8 @@ protected function writeSpreadsheet(PhpPresentation $presentation, Chart $chart,
         }
         $spreadsheet->getProperties()
             ->setCreator(
-                $presentation->getDocumentProperties()->getCreator())->setLastModifiedBy(
+                $presentation->getDocumentProperties()->getCreator()
+            )->setLastModifiedBy(
                     $presentation->getDocumentProperties()->getLastModifiedBy()
                 )
             ->setTitle($title);
@@ -368,7 +363,7 @@ protected function writeMultipleValuesOrReference(XMLWriter $objWriter, bool $is
                 // c:pt
                 $objWriter->startElement('c:pt');
                 $objWriter->writeAttribute('idx', $i);
-                $objWriter->writeElement('c:v', strval($values[$i]));
+                $objWriter->writeElement('c:v', (string) ($values[$i]));
                 $objWriter->endElement();
             }
         } else {
@@ -386,7 +381,7 @@ protected function writeMultipleValuesOrReference(XMLWriter $objWriter, bool $is
                 // c:pt
                 $objWriter->startElement('c:pt');
                 $objWriter->writeAttribute('idx', $i);
-                $objWriter->writeElement('c:v', strval($values[$i]));
+                $objWriter->writeElement('c:v', (string) ($values[$i]));
                 $objWriter->endElement();
             }
 
@@ -397,7 +392,7 @@ protected function writeMultipleValuesOrReference(XMLWriter $objWriter, bool $is
     }
 
     /**
-     * Write Title
+     * Write Title.
      */
     protected function writeTitle(XMLWriter $objWriter, Title $subject): void
     {
@@ -494,8 +489,6 @@ protected function writeTitle(XMLWriter $objWriter, Title $subject): void
      * Write Plot Area.
      *
      * @param XMLWriter $objWriter XML Writer
-     *
-     * @throws UndefinedChartTypeException
      */
     protected function writePlotArea(XMLWriter $objWriter, PlotArea $subject, Chart $chart): void
     {
@@ -700,7 +693,6 @@ protected function writeLayout(XMLWriter $objWriter, $subject): void
      *
      * @param XMLWriter $objWriter XML Writer
      * @param Chart\Type\Area $subject
-     * @param bool $includeSheet
      */
     protected function writeTypeArea(XMLWriter $objWriter, Area $subject, bool $includeSheet = false): void
     {
@@ -802,7 +794,6 @@ protected function writeTypeArea(XMLWriter $objWriter, Area $subject, bool $incl
      *
      * @param XMLWriter $objWriter XML Writer
      * @param Chart\Type\Bar $subject
-     * @param bool $includeSheet
      */
     protected function writeTypeBar(XMLWriter $objWriter, Bar $subject, bool $includeSheet = false): void
     {
@@ -1014,7 +1005,6 @@ protected function writeTypeBar(XMLWriter $objWriter, Bar $subject, bool $includ
      *
      * @param XMLWriter $objWriter XML Writer
      * @param Chart\Type\Bar3D $subject
-     * @param bool $includeSheet
      */
     protected function writeTypeBar3D(XMLWriter $objWriter, Bar3D $subject, bool $includeSheet = false): void
     {
@@ -1206,8 +1196,6 @@ protected function writeTypeBar3D(XMLWriter $objWriter, Bar3D $subject, bool $in
      * Write Type Pie.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param Doughnut $subject
-     * @param bool $includeSheet
      */
     protected function writeTypeDoughnut(XMLWriter $objWriter, Doughnut $subject, bool $includeSheet = false): void
     {
@@ -1365,8 +1353,6 @@ protected function writeTypeDoughnut(XMLWriter $objWriter, Doughnut $subject, bo
      * Write Type Pie.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param Pie $subject
-     * @param bool $includeSheet
      */
     protected function writeTypePie(XMLWriter $objWriter, Pie $subject, bool $includeSheet = false): void
     {
@@ -1530,8 +1516,6 @@ protected function writeTypePie(XMLWriter $objWriter, Pie $subject, bool $includ
      * Write Type Pie3D.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param Pie3D $subject
-     * @param bool $includeSheet
      */
     protected function writeTypePie3D(XMLWriter $objWriter, Pie3D $subject, bool $includeSheet = false): void
     {
@@ -1689,8 +1673,6 @@ protected function writeTypePie3D(XMLWriter $objWriter, Pie3D $subject, bool $in
      * Write Type Line.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param Line $subject
-     * @param bool $includeSheet
      */
     protected function writeTypeLine(XMLWriter $objWriter, Line $subject, bool $includeSheet = false): void
     {
@@ -1855,11 +1837,9 @@ protected function writeTypeLine(XMLWriter $objWriter, Line $subject, bool $incl
     }
 
     /**
-     * Write Type Radar
+     * Write Type Radar.
      *
      * @param XMLWriter $objWriter XML Writer
-     * @param Radar $subject
-     * @param bool $includeSheet
      */
     protected function writeTypeRadar(XMLWriter $objWriter, Radar $subject, bool $includeSheet = false): void
     {
@@ -2026,11 +2006,7 @@ protected function writeTypeRadar(XMLWriter $objWriter, Radar $subject, bool $in
     }
 
     /**
-     * Write Type Scatter
-     *
-     * @param XMLWriter $objWriter
-     * @param Scatter $subject
-     * @param bool $includeSheet
+     * Write Type Scatter.
      */
     protected function writeTypeScatter(XMLWriter $objWriter, Scatter $subject, bool $includeSheet = false): void
     {
@@ -2206,8 +2182,6 @@ protected function writeTypeScatter(XMLWriter $objWriter, Scatter $subject, bool
     /**
      * Write chart relationships to XML format.
      *
-     * @param Chart $pChart
-     *
      * @return string XML Output
      */
     protected function writeChartRelationships(Chart $pChart): string
@@ -2233,10 +2207,6 @@ protected function writeChartRelationships(Chart $pChart): string
         return $objWriter->getData();
     }
 
-    /**
-     * @param XMLWriter $objWriter
-     * @param Chart\Marker $marker
-     */
     protected function writeSeriesMarker(XMLWriter $objWriter, Chart\Marker $marker): void
     {
         // c:marker
@@ -2276,12 +2246,6 @@ protected function writeSeriesMarker(XMLWriter $objWriter, Chart\Marker $marker)
         $objWriter->endElement();
     }
 
-    /**
-     * @param XMLWriter $objWriter
-     * @param Chart\Axis $oAxis
-     * @param string $typeAxis
-     * @param Chart\Type\AbstractType $typeChart
-     */
     protected function writeAxis(XMLWriter $objWriter, Chart\Axis $oAxis, string $typeAxis, Chart\Type\AbstractType $typeChart): void
     {
         if (Chart\Axis::AXIS_X != $typeAxis && Chart\Axis::AXIS_Y != $typeAxis) {
@@ -2539,10 +2503,6 @@ protected function writeAxis(XMLWriter $objWriter, Chart\Axis $oAxis, string $ty
         $objWriter->endElement();
     }
 
-    /**
-     * @param XMLWriter $objWriter
-     * @param Gridlines $oGridlines
-     */
     protected function writeAxisGridlines(XMLWriter $objWriter, Gridlines $oGridlines): void
     {
         // c:spPr
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptComments.php b/src/PhpPresentation/Writer/PowerPoint2007/PptComments.php
index 5a30c08a4b..e585cd2472 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptComments.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptComments.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -28,9 +27,6 @@
 
 class PptComments extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         foreach ($this->getPresentation()->getAllSlides() as $numSlide => $oSlide) {
@@ -44,9 +40,6 @@ public function render(): ZipInterface
         return $this->getZip();
     }
 
-    /**
-     * @return string
-     */
     protected function writeSlideComments(Slide $oSlide): string
     {
         /**
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptMedia.php b/src/PhpPresentation/Writer/PowerPoint2007/PptMedia.php
index 85a7acecc1..13caebfedc 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptMedia.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptMedia.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -25,9 +24,6 @@
 
 class PptMedia extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         for ($i = 0; $i < $this->getDrawingHashTable()->count(); ++$i) {
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptPresProps.php b/src/PhpPresentation/Writer/PowerPoint2007/PptPresProps.php
index c28f12d22f..05f0103d2d 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptPresProps.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptPresProps.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -25,9 +24,6 @@
 
 class PptPresProps extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         $presentationPpts = $this->oPresentation->getPresentationProperties();
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptPresentation.php b/src/PhpPresentation/Writer/PowerPoint2007/PptPresentation.php
index a6aa3c1336..6f93dd4660 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptPresentation.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptPresentation.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -26,9 +25,6 @@
 
 class PptPresentation extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         // Create XML writer
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptSlideLayouts.php b/src/PhpPresentation/Writer/PowerPoint2007/PptSlideLayouts.php
index b482579d79..58a718a04b 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptSlideLayouts.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptSlideLayouts.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -30,9 +29,6 @@
 
 class PptSlideLayouts extends AbstractSlide
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         foreach ($this->oPresentation->getAllMasterSlides() as $oSlideMaster) {
@@ -181,7 +177,7 @@ protected function writeSlideLayout(SlideLayout $pSlideLayout): string
         // p:sldLayout\p:clrMapOvr\
         $objWriter->endElement();
 
-        if (!is_null($pSlideLayout->getTransition())) {
+        if (null !== $pSlideLayout->getTransition()) {
             $this->writeSlideTransition($objWriter, $pSlideLayout->getTransition());
         }
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptSlideMasters.php b/src/PhpPresentation/Writer/PowerPoint2007/PptSlideMasters.php
index a7758a8984..9a266ad013 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptSlideMasters.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptSlideMasters.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -30,9 +29,6 @@
 
 class PptSlideMasters extends AbstractSlide
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         foreach ($this->oPresentation->getAllMasterSlides() as $oMasterSlide) {
@@ -178,7 +174,7 @@ protected function writeSlideMaster(SlideMaster $pSlide): string
         // p:sldMaster\p:sldLayoutIdLst
         $objWriter->startElement('p:sldLayoutIdLst');
         foreach ($pSlide->getAllSlideLayouts() as $layout) {
-            /* @var $layout Slide\SlideLayout */
+            // @var $layout Slide\SlideLayout
             $objWriter->startElement('p:sldLayoutId');
             $objWriter->writeAttribute('id', $layout->layoutId);
             $objWriter->writeAttribute('r:id', $layout->relationId);
@@ -237,7 +233,7 @@ protected function writeSlideMaster(SlideMaster $pSlide): string
         $objWriter->endElement();
         // p:sldMaster\p:txStyles\
 
-        if (!is_null($pSlide->getTransition())) {
+        if (null !== $pSlide->getTransition()) {
             $this->writeSlideTransition($objWriter, $pSlide->getTransition());
         }
 
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptSlides.php b/src/PhpPresentation/Writer/PowerPoint2007/PptSlides.php
index 8c2999d04a..7e29fc0da3 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptSlides.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptSlides.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -40,8 +39,6 @@ class PptSlides extends AbstractSlide
 {
     /**
      * Add slides (drawings, ...) and slide relationships (drawings, ...).
-     *
-     * @return ZipInterface
      */
     public function render(): ZipInterface
     {
@@ -331,12 +328,14 @@ protected function writeSlideRelationships(Slide $pSlide): string
             while ($iterator->valid()) {
                 if ($iterator->current() instanceof Comment) {
                     $hasSlideComment = true;
+
                     break;
                 } elseif ($iterator->current() instanceof Group) {
                     $iterator2 = $iterator->current()->getShapeCollection()->getIterator();
                     while ($iterator2->valid()) {
                         if ($iterator2->current() instanceof Comment) {
                             $hasSlideComment = true;
+
                             break 2;
                         }
                         $iterator2->next();
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptTableProps.php b/src/PhpPresentation/Writer/PowerPoint2007/PptTableProps.php
index ff2c5f851f..f92f6ddb3a 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptTableProps.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptTableProps.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -25,9 +24,6 @@
 
 class PptTableProps extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         // Create XML writer
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptTheme.php b/src/PhpPresentation/Writer/PowerPoint2007/PptTheme.php
index c2c9e8e9b5..9b53b7c1c1 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptTheme.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptTheme.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -26,9 +25,6 @@
 
 class PptTheme extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         foreach ($this->oPresentation->getAllMasterSlides() as $oMasterSlide) {
@@ -80,7 +76,7 @@ protected function writeTheme(Slide\SlideMaster $oMasterSlide): string
         // Create XML writer
         $objWriter = new XMLWriter(XMLWriter::STORAGE_MEMORY);
 
-        $name = 'Theme' . rand(1, 100);
+        $name = 'Theme' . mt_rand(1, 100);
 
         // XML header
         $objWriter->startDocument('1.0', 'UTF-8', 'yes');
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/PptViewProps.php b/src/PhpPresentation/Writer/PowerPoint2007/PptViewProps.php
index 2a89473843..17891a69a8 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/PptViewProps.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/PptViewProps.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -25,9 +24,6 @@
 
 class PptViewProps extends AbstractDecoratorWriter
 {
-    /**
-     * @return ZipInterface
-     */
     public function render(): ZipInterface
     {
         // Create XML writer
diff --git a/src/PhpPresentation/Writer/PowerPoint2007/Relationships.php b/src/PhpPresentation/Writer/PowerPoint2007/Relationships.php
index 9069ed485f..58eb325dde 100644
--- a/src/PhpPresentation/Writer/PowerPoint2007/Relationships.php
+++ b/src/PhpPresentation/Writer/PowerPoint2007/Relationships.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -29,8 +28,6 @@ class Relationships extends AbstractDecoratorWriter
 {
     /**
      * Add relationships to ZIP file.
-     *
-     * @return ZipInterface
      */
     public function render(): ZipInterface
     {
@@ -134,6 +131,7 @@ protected function writePresentationRelationships(): string
                     continue;
                 }
                 $this->writeRelationship($objWriter, $relationId++, 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/commentAuthors', 'commentAuthors.xml');
+
                 break 2;
             }
         }
diff --git a/src/PhpPresentation/Writer/Serialized.php b/src/PhpPresentation/Writer/Serialized.php
index 5482c1e2ee..ea556a8464 100644
--- a/src/PhpPresentation/Writer/Serialized.php
+++ b/src/PhpPresentation/Writer/Serialized.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -38,7 +37,7 @@ class Serialized extends AbstractWriter implements WriterInterface
      *
      * @param \PhpOffice\PhpPresentation\PhpPresentation $pPhpPresentation
      */
-    public function __construct(PhpPresentation $pPhpPresentation = null)
+    public function __construct(?PhpPresentation $pPhpPresentation = null)
     {
         // Set PhpPresentation
         $this->setPhpPresentation($pPhpPresentation ?? new PhpPresentation());
@@ -49,9 +48,6 @@ public function __construct(PhpPresentation $pPhpPresentation = null)
 
     /**
      * Save PhpPresentation to file.
-     *
-     * @throws DirectoryNotFoundException
-     * @throws InvalidParameterException
      */
     public function save(string $pFilename): void
     {
@@ -93,12 +89,11 @@ public function save(string $pFilename): void
     /**
      * Serialize PhpPresentation object to XML.
      *
-     * @param PhpPresentation|null $pPhpPresentation
      * @param string $pFilename
      *
      * @return string XML Output
      */
-    protected function writeSerialized(PhpPresentation $pPhpPresentation = null, $pFilename = '')
+    protected function writeSerialized(?PhpPresentation $pPhpPresentation = null, $pFilename = '')
     {
         // Clone $pPhpPresentation
         $pPhpPresentation = clone $pPhpPresentation;
diff --git a/src/PhpPresentation/Writer/WriterInterface.php b/src/PhpPresentation/Writer/WriterInterface.php
index ab64192e1a..7c04b7adbf 100644
--- a/src/PhpPresentation/Writer/WriterInterface.php
+++ b/src/PhpPresentation/Writer/WriterInterface.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -26,7 +25,7 @@
 interface WriterInterface
 {
     /**
-     * Save PhpPresentation to file
+     * Save PhpPresentation to file.
      */
     public function save(string $pFilename): void;
 }
diff --git a/tests/PhpPresentation/Tests/AbstractShapeTest.php b/tests/PhpPresentation/Tests/AbstractShapeTest.php
index 8cb097b2d5..d254cc5eb7 100644
--- a/tests/PhpPresentation/Tests/AbstractShapeTest.php
+++ b/tests/PhpPresentation/Tests/AbstractShapeTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -43,25 +42,25 @@ public function testConstruct(): void
     {
         $object = new RichText();
 
-        $this->assertEquals(0, $object->getOffsetX());
-        $this->assertEquals(0, $object->getOffsetY());
-        $this->assertEquals(0, $object->getHeight());
-        $this->assertEquals(0, $object->getRotation());
-        $this->assertEquals(0, $object->getWidth());
-        $this->assertInstanceOf(Border::class, $object->getBorder());
-        $this->assertEquals(Border::LINE_NONE, $object->getBorder()->getLineStyle());
-        $this->assertInstanceOf(Fill::class, $object->getFill());
-        $this->assertInstanceOf(Shadow::class, $object->getShadow());
+        self::assertEquals(0, $object->getOffsetX());
+        self::assertEquals(0, $object->getOffsetY());
+        self::assertEquals(0, $object->getHeight());
+        self::assertEquals(0, $object->getRotation());
+        self::assertEquals(0, $object->getWidth());
+        self::assertInstanceOf(Border::class, $object->getBorder());
+        self::assertEquals(Border::LINE_NONE, $object->getBorder()->getLineStyle());
+        self::assertInstanceOf(Fill::class, $object->getFill());
+        self::assertInstanceOf(Shadow::class, $object->getShadow());
     }
 
     public function testFill(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(AbstractShape::class, $object->setFill());
-        $this->assertNull($object->getFill());
-        $this->assertInstanceOf(AbstractShape::class, $object->setFill(new Fill()));
-        $this->assertInstanceOf(Fill::class, $object->getFill());
+        self::assertInstanceOf(AbstractShape::class, $object->setFill());
+        self::assertNull($object->getFill());
+        self::assertInstanceOf(AbstractShape::class, $object->setFill(new Fill()));
+        self::assertInstanceOf(Fill::class, $object->getFill());
     }
 
     public function testHeight(): void
@@ -69,24 +68,24 @@ public function testHeight(): void
         $object = new RichText();
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(AbstractShape::class, $object->setHeight());
-        $this->assertEquals(0, $object->getHeight());
-        $this->assertInstanceOf(AbstractShape::class, $object->setHeight($value));
-        $this->assertEquals($value, $object->getHeight());
+        self::assertInstanceOf(AbstractShape::class, $object->setHeight());
+        self::assertEquals(0, $object->getHeight());
+        self::assertInstanceOf(AbstractShape::class, $object->setHeight($value));
+        self::assertEquals($value, $object->getHeight());
     }
 
     public function testHyperlink(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(AbstractShape::class, $object->setHyperlink());
-        $this->assertFalse($object->hasHyperlink());
-        $this->assertInstanceOf(Hyperlink::class, $object->getHyperlink());
-        $this->assertTrue($object->hasHyperlink());
-        $this->assertInstanceOf(AbstractShape::class, $object->setHyperlink(new Hyperlink('http://www.google.fr')));
-        $this->assertTrue($object->hasHyperlink());
-        $this->assertInstanceOf(Hyperlink::class, $object->getHyperlink());
-        $this->assertTrue($object->hasHyperlink());
+        self::assertInstanceOf(AbstractShape::class, $object->setHyperlink());
+        self::assertFalse($object->hasHyperlink());
+        self::assertInstanceOf(Hyperlink::class, $object->getHyperlink());
+        self::assertTrue($object->hasHyperlink());
+        self::assertInstanceOf(AbstractShape::class, $object->setHyperlink(new Hyperlink('http://www.google.fr')));
+        self::assertTrue($object->hasHyperlink());
+        self::assertInstanceOf(Hyperlink::class, $object->getHyperlink());
+        self::assertTrue($object->hasHyperlink());
     }
 
     public function testOffsetX(): void
@@ -94,10 +93,10 @@ public function testOffsetX(): void
         $object = new RichText();
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(AbstractShape::class, $object->setOffsetX());
-        $this->assertEquals(0, $object->getOffsetX());
-        $this->assertInstanceOf(AbstractShape::class, $object->setOffsetX($value));
-        $this->assertEquals($value, $object->getOffsetX());
+        self::assertInstanceOf(AbstractShape::class, $object->setOffsetX());
+        self::assertEquals(0, $object->getOffsetX());
+        self::assertInstanceOf(AbstractShape::class, $object->setOffsetX($value));
+        self::assertEquals($value, $object->getOffsetX());
     }
 
     public function testOffsetY(): void
@@ -105,10 +104,10 @@ public function testOffsetY(): void
         $object = new RichText();
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(AbstractShape::class, $object->setOffsetY());
-        $this->assertEquals(0, $object->getOffsetY());
-        $this->assertInstanceOf(AbstractShape::class, $object->setOffsetY($value));
-        $this->assertEquals($value, $object->getOffsetY());
+        self::assertInstanceOf(AbstractShape::class, $object->setOffsetY());
+        self::assertEquals(0, $object->getOffsetY());
+        self::assertInstanceOf(AbstractShape::class, $object->setOffsetY($value));
+        self::assertEquals($value, $object->getOffsetY());
     }
 
     public function testRotation(): void
@@ -116,20 +115,20 @@ public function testRotation(): void
         $object = new RichText();
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(AbstractShape::class, $object->setRotation());
-        $this->assertEquals(0, $object->getRotation());
-        $this->assertInstanceOf(AbstractShape::class, $object->setRotation($value));
-        $this->assertEquals($value, $object->getRotation());
+        self::assertInstanceOf(AbstractShape::class, $object->setRotation());
+        self::assertEquals(0, $object->getRotation());
+        self::assertInstanceOf(AbstractShape::class, $object->setRotation($value));
+        self::assertEquals($value, $object->getRotation());
     }
 
     public function testShadow(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(AbstractShape::class, $object->setShadow());
-        $this->assertNull($object->getShadow());
-        $this->assertInstanceOf(AbstractShape::class, $object->setShadow(new Shadow()));
-        $this->assertInstanceOf(Shadow::class, $object->getShadow());
+        self::assertInstanceOf(AbstractShape::class, $object->setShadow());
+        self::assertNull($object->getShadow());
+        self::assertInstanceOf(AbstractShape::class, $object->setShadow(new Shadow()));
+        self::assertInstanceOf(Shadow::class, $object->getShadow());
     }
 
     public function testWidth(): void
@@ -137,10 +136,10 @@ public function testWidth(): void
         $object = new RichText();
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(AbstractShape::class, $object->setWidth());
-        $this->assertEquals(0, $object->getWidth());
-        $this->assertInstanceOf(AbstractShape::class, $object->setWidth($value));
-        $this->assertEquals($value, $object->getWidth());
+        self::assertInstanceOf(AbstractShape::class, $object->setWidth());
+        self::assertEquals(0, $object->getWidth());
+        self::assertInstanceOf(AbstractShape::class, $object->setWidth($value));
+        self::assertEquals($value, $object->getWidth());
     }
 
     public function testWidthAndHeight(): void
@@ -148,38 +147,38 @@ public function testWidthAndHeight(): void
         $object = new RichText();
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(AbstractShape::class, $object->setWidthAndHeight());
-        $this->assertEquals(0, $object->getWidth());
-        $this->assertEquals(0, $object->getHeight());
-        $this->assertInstanceOf(AbstractShape::class, $object->setWidthAndHeight($value));
-        $this->assertEquals($value, $object->getWidth());
-        $this->assertEquals(0, $object->getHeight());
-        $this->assertInstanceOf(AbstractShape::class, $object->setWidthAndHeight($value, $value));
-        $this->assertEquals($value, $object->getWidth());
-        $this->assertEquals($value, $object->getHeight());
+        self::assertInstanceOf(AbstractShape::class, $object->setWidthAndHeight());
+        self::assertEquals(0, $object->getWidth());
+        self::assertEquals(0, $object->getHeight());
+        self::assertInstanceOf(AbstractShape::class, $object->setWidthAndHeight($value));
+        self::assertEquals($value, $object->getWidth());
+        self::assertEquals(0, $object->getHeight());
+        self::assertInstanceOf(AbstractShape::class, $object->setWidthAndHeight($value, $value));
+        self::assertEquals($value, $object->getWidth());
+        self::assertEquals($value, $object->getHeight());
     }
 
     public function testPlaceholder(): void
     {
         $object = new RichText();
-        $this->assertFalse($object->isPlaceholder(), 'Standard Shape should not be a placeholder object');
-        $this->assertNull($object->getPlaceholder());
-        $this->assertInstanceOf(
+        self::assertFalse($object->isPlaceholder(), 'Standard Shape should not be a placeholder object');
+        self::assertNull($object->getPlaceholder());
+        self::assertInstanceOf(
             AbstractShape::class,
             $object->setPlaceHolder(new Placeholder(Placeholder::PH_TYPE_TITLE))
         );
-        $this->assertTrue($object->isPlaceholder());
-        $this->assertInstanceOf(Placeholder::class, $object->getPlaceholder());
-        $this->assertEquals('title', $object->getPlaceholder()->getType());
+        self::assertTrue($object->isPlaceholder());
+        self::assertInstanceOf(Placeholder::class, $object->getPlaceholder());
+        self::assertEquals('title', $object->getPlaceholder()->getType());
 
         $object = new RichText();
-        $this->assertFalse($object->isPlaceholder(), 'Standard Shape should not be a placeholder object');
+        self::assertFalse($object->isPlaceholder(), 'Standard Shape should not be a placeholder object');
         $placeholder = new Placeholder(Placeholder::PH_TYPE_TITLE);
         $placeholder->setType(Placeholder::PH_TYPE_SUBTITLE);
-        $this->assertInstanceOf(AbstractShape::class, $object->setPlaceHolder($placeholder));
-        $this->assertTrue($object->isPlaceholder());
-        $this->assertInstanceOf(Placeholder::class, $object->getPlaceholder());
-        $this->assertEquals('subTitle', $object->getPlaceholder()->getType());
+        self::assertInstanceOf(AbstractShape::class, $object->setPlaceHolder($placeholder));
+        self::assertTrue($object->isPlaceholder());
+        self::assertInstanceOf(Placeholder::class, $object->getPlaceholder());
+        self::assertEquals('subTitle', $object->getPlaceholder()->getType());
     }
 
     public function testContainer(): void
@@ -190,11 +189,11 @@ public function testContainer(): void
         $oSlide = new Slide();
         $oSlide->addShape($object2);
 
-        $this->assertNull($object->getContainer());
-        $this->assertInstanceOf(AbstractShape::class, $object->setContainer($oSlide));
-        $this->assertInstanceOf(Slide::class, $object->getContainer());
-        $this->assertInstanceOf(AbstractShape::class, $object->setContainer(null, true));
-        $this->assertNull($object->getContainer());
+        self::assertNull($object->getContainer());
+        self::assertInstanceOf(AbstractShape::class, $object->setContainer($oSlide));
+        self::assertInstanceOf(Slide::class, $object->getContainer());
+        self::assertInstanceOf(AbstractShape::class, $object->setContainer(null, true));
+        self::assertNull($object->getContainer());
     }
 
     public function testContainerException(): void
@@ -202,9 +201,9 @@ public function testContainerException(): void
         $object = new RichText();
         $oSlide = new Slide();
 
-        $this->assertNull($object->getContainer());
-        $this->assertInstanceOf(AbstractShape::class, $object->setContainer($oSlide));
-        $this->assertInstanceOf(Slide::class, $object->getContainer());
+        self::assertNull($object->getContainer());
+        self::assertInstanceOf(AbstractShape::class, $object->setContainer($oSlide));
+        self::assertInstanceOf(Slide::class, $object->getContainer());
         $this->expectException(ShapeContainerAlreadyAssignedException::class);
         $this->expectExceptionMessage('The shape PhpOffice\PhpPresentation\AbstractShape has already a container assigned');
         $object->setContainer(null);
diff --git a/tests/PhpPresentation/Tests/AutoloaderTest.php b/tests/PhpPresentation/Tests/AutoloaderTest.php
index c1b32c0c4e..a93e5f4a0c 100644
--- a/tests/PhpPresentation/Tests/AutoloaderTest.php
+++ b/tests/PhpPresentation/Tests/AutoloaderTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -34,7 +33,7 @@ class AutoloaderTest extends TestCase
     public function testRegister(): void
     {
         Autoloader::register();
-        $this->assertContains(
+        self::assertContains(
             ['PhpOffice\\PhpPresentation\\Autoloader', 'autoload'],
             spl_autoload_functions()
         );
@@ -48,7 +47,7 @@ public function testAutoload(): void
         $declared = get_declared_classes();
         $declaredCount = count($declared);
         Autoloader::autoload('Foo');
-        $this->assertEquals(
+        self::assertEquals(
             $declaredCount,
             count(get_declared_classes()),
             'PhpOffice\\PhpPresentation\\Autoloader::autoload() is trying to load ' .
diff --git a/tests/PhpPresentation/Tests/DocumentLayoutTest.php b/tests/PhpPresentation/Tests/DocumentLayoutTest.php
index 1d1c1c4883..58351938db 100644
--- a/tests/PhpPresentation/Tests/DocumentLayoutTest.php
+++ b/tests/PhpPresentation/Tests/DocumentLayoutTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,9 +36,9 @@ public function testConstruct(): void
     {
         $object = new DocumentLayout();
 
-        $this->assertEquals('screen4x3', $object->getDocumentLayout());
-        $this->assertEquals(9144000, $object->getCX());
-        $this->assertEquals(6858000, $object->getCY());
+        self::assertEquals('screen4x3', $object->getDocumentLayout());
+        self::assertEquals(9144000, $object->getCX());
+        self::assertEquals(6858000, $object->getCY());
     }
 
     /**
@@ -49,52 +48,52 @@ public function testSetCustomLayout(): void
     {
         $object = new DocumentLayout();
         $object->setDocumentLayout(['cx' => 6858000, 'cy' => 9144000], false);
-        $this->assertEquals(DocumentLayout::LAYOUT_CUSTOM, $object->getDocumentLayout());
-        $this->assertEquals(9144000, $object->getCX());
-        $this->assertEquals(6858000, $object->getCY());
+        self::assertEquals(DocumentLayout::LAYOUT_CUSTOM, $object->getDocumentLayout());
+        self::assertEquals(9144000, $object->getCX());
+        self::assertEquals(6858000, $object->getCY());
         $object->setDocumentLayout(['cx' => 6858000, 'cy' => 9144000], true);
-        $this->assertEquals(DocumentLayout::LAYOUT_CUSTOM, $object->getDocumentLayout());
-        $this->assertEquals(6858000, $object->getCX());
-        $this->assertEquals(9144000, $object->getCY());
+        self::assertEquals(DocumentLayout::LAYOUT_CUSTOM, $object->getDocumentLayout());
+        self::assertEquals(6858000, $object->getCX());
+        self::assertEquals(9144000, $object->getCY());
     }
 
     public function testCX(): void
     {
         $value = mt_rand(1, 100000);
         $object = new DocumentLayout();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value));
-        $this->assertEquals($value, $object->getCX());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_CENTIMETER));
-        $this->assertEquals($value, $object->getCX(DocumentLayout::UNIT_CENTIMETER));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_EMU));
-        $this->assertEquals($value, $object->getCX(DocumentLayout::UNIT_EMU));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_INCH));
-        $this->assertEquals($value, $object->getCX(DocumentLayout::UNIT_INCH));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_MILLIMETER));
-        $this->assertEquals($value, $object->getCX(DocumentLayout::UNIT_MILLIMETER));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_POINT));
-        $this->assertEquals($value, $object->getCX(DocumentLayout::UNIT_POINT));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_PIXEL));
-        $this->assertEquals($value, $object->getCX(DocumentLayout::UNIT_PIXEL));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value));
+        self::assertEquals($value, $object->getCX());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_CENTIMETER));
+        self::assertEquals($value, $object->getCX(DocumentLayout::UNIT_CENTIMETER));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_EMU));
+        self::assertEquals($value, $object->getCX(DocumentLayout::UNIT_EMU));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_INCH));
+        self::assertEquals($value, $object->getCX(DocumentLayout::UNIT_INCH));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_MILLIMETER));
+        self::assertEquals($value, $object->getCX(DocumentLayout::UNIT_MILLIMETER));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_POINT));
+        self::assertEquals($value, $object->getCX(DocumentLayout::UNIT_POINT));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCX($value, DocumentLayout::UNIT_PIXEL));
+        self::assertEquals($value, $object->getCX(DocumentLayout::UNIT_PIXEL));
     }
 
     public function testCY(): void
     {
         $value = mt_rand(1, 100000);
         $object = new DocumentLayout();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value));
-        $this->assertEquals($value, $object->getCY());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_CENTIMETER));
-        $this->assertEquals($value, $object->getCY(DocumentLayout::UNIT_CENTIMETER));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_EMU));
-        $this->assertEquals($value, $object->getCY(DocumentLayout::UNIT_EMU));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_INCH));
-        $this->assertEquals($value, $object->getCY(DocumentLayout::UNIT_INCH));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_MILLIMETER));
-        $this->assertEquals($value, $object->getCY(DocumentLayout::UNIT_MILLIMETER));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_POINT));
-        $this->assertEquals($value, $object->getCY(DocumentLayout::UNIT_POINT));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_PIXEL));
-        $this->assertEquals($value, $object->getCY(DocumentLayout::UNIT_PIXEL));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value));
+        self::assertEquals($value, $object->getCY());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_CENTIMETER));
+        self::assertEquals($value, $object->getCY(DocumentLayout::UNIT_CENTIMETER));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_EMU));
+        self::assertEquals($value, $object->getCY(DocumentLayout::UNIT_EMU));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_INCH));
+        self::assertEquals($value, $object->getCY(DocumentLayout::UNIT_INCH));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_MILLIMETER));
+        self::assertEquals($value, $object->getCY(DocumentLayout::UNIT_MILLIMETER));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_POINT));
+        self::assertEquals($value, $object->getCY(DocumentLayout::UNIT_POINT));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentLayout', $object->setCY($value, DocumentLayout::UNIT_PIXEL));
+        self::assertEquals($value, $object->getCY(DocumentLayout::UNIT_PIXEL));
     }
 }
diff --git a/tests/PhpPresentation/Tests/DocumentPropertiesTest.php b/tests/PhpPresentation/Tests/DocumentPropertiesTest.php
index 3e520d0457..5d0b372593 100644
--- a/tests/PhpPresentation/Tests/DocumentPropertiesTest.php
+++ b/tests/PhpPresentation/Tests/DocumentPropertiesTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -53,7 +52,7 @@ public function testGetSet(): void
             $get = "get{$key}";
             $set = "set{$key}";
             $object->$set($val);
-            $this->assertEquals($val, $object->$get());
+            self::assertEquals($val, $object->$get());
         }
     }
 
@@ -73,7 +72,7 @@ public function testGetSetNull(): void
             $get = "get{$key}";
             $set = "set{$key}";
             $object->$set();
-            $this->assertEquals($time, $object->$get());
+            self::assertEquals($time, $object->$get());
         }
     }
 
@@ -82,52 +81,52 @@ public function testCustomProperties(): void
         $valueTime = time();
 
         $object = new DocumentProperties();
-        $this->assertIsArray($object->getCustomProperties());
-        $this->assertCount(0, $object->getCustomProperties());
-        $this->assertFalse($object->isCustomPropertySet('pName'));
-        $this->assertNull($object->getCustomPropertyType('pName'));
-        $this->assertNull($object->getCustomPropertyValue('pName'));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', 'pValue', null));
-        $this->assertCount(1, $object->getCustomProperties());
-        $this->assertTrue($object->isCustomPropertySet('pName'));
-        $this->assertEquals(DocumentProperties::PROPERTY_TYPE_STRING, $object->getCustomPropertyType('pName'));
-        $this->assertEquals('pValue', $object->getCustomPropertyValue('pName'));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', 2, null));
-        $this->assertCount(1, $object->getCustomProperties());
-        $this->assertTrue($object->isCustomPropertySet('pName'));
-        $this->assertEquals(DocumentProperties::PROPERTY_TYPE_INTEGER, $object->getCustomPropertyType('pName'));
-        $this->assertEquals(2, $object->getCustomPropertyValue('pName'));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', 2.1, null));
-        $this->assertCount(1, $object->getCustomProperties());
-        $this->assertTrue($object->isCustomPropertySet('pName'));
-        $this->assertEquals(DocumentProperties::PROPERTY_TYPE_FLOAT, $object->getCustomPropertyType('pName'));
-        $this->assertEquals(2.1, $object->getCustomPropertyValue('pName'));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', true, null));
-        $this->assertCount(1, $object->getCustomProperties());
-        $this->assertTrue($object->isCustomPropertySet('pName'));
-        $this->assertEquals(DocumentProperties::PROPERTY_TYPE_BOOLEAN, $object->getCustomPropertyType('pName'));
-        $this->assertEquals(true, $object->getCustomPropertyValue('pName'));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', null, null));
-        $this->assertCount(1, $object->getCustomProperties());
-        $this->assertTrue($object->isCustomPropertySet('pName'));
-        $this->assertEquals(DocumentProperties::PROPERTY_TYPE_STRING, $object->getCustomPropertyType('pName'));
-        $this->assertEquals(null, $object->getCustomPropertyValue('pName'));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', $valueTime, DocumentProperties::PROPERTY_TYPE_DATE));
-        $this->assertCount(1, $object->getCustomProperties());
-        $this->assertTrue($object->isCustomPropertySet('pName'));
-        $this->assertEquals(DocumentProperties::PROPERTY_TYPE_DATE, $object->getCustomPropertyType('pName'));
-        $this->assertEquals($valueTime, $object->getCustomPropertyValue('pName'));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', (string) $valueTime, DocumentProperties::PROPERTY_TYPE_UNKNOWN));
-        $this->assertCount(1, $object->getCustomProperties());
-        $this->assertTrue($object->isCustomPropertySet('pName'));
-        $this->assertEquals(DocumentProperties::PROPERTY_TYPE_STRING, $object->getCustomPropertyType('pName'));
-        $this->assertEquals($valueTime, $object->getCustomPropertyValue('pName'));
+        self::assertIsArray($object->getCustomProperties());
+        self::assertCount(0, $object->getCustomProperties());
+        self::assertFalse($object->isCustomPropertySet('pName'));
+        self::assertNull($object->getCustomPropertyType('pName'));
+        self::assertNull($object->getCustomPropertyValue('pName'));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', 'pValue', null));
+        self::assertCount(1, $object->getCustomProperties());
+        self::assertTrue($object->isCustomPropertySet('pName'));
+        self::assertEquals(DocumentProperties::PROPERTY_TYPE_STRING, $object->getCustomPropertyType('pName'));
+        self::assertEquals('pValue', $object->getCustomPropertyValue('pName'));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', 2, null));
+        self::assertCount(1, $object->getCustomProperties());
+        self::assertTrue($object->isCustomPropertySet('pName'));
+        self::assertEquals(DocumentProperties::PROPERTY_TYPE_INTEGER, $object->getCustomPropertyType('pName'));
+        self::assertEquals(2, $object->getCustomPropertyValue('pName'));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', 2.1, null));
+        self::assertCount(1, $object->getCustomProperties());
+        self::assertTrue($object->isCustomPropertySet('pName'));
+        self::assertEquals(DocumentProperties::PROPERTY_TYPE_FLOAT, $object->getCustomPropertyType('pName'));
+        self::assertEquals(2.1, $object->getCustomPropertyValue('pName'));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', true, null));
+        self::assertCount(1, $object->getCustomProperties());
+        self::assertTrue($object->isCustomPropertySet('pName'));
+        self::assertEquals(DocumentProperties::PROPERTY_TYPE_BOOLEAN, $object->getCustomPropertyType('pName'));
+        self::assertTrue($object->getCustomPropertyValue('pName'));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', null, null));
+        self::assertCount(1, $object->getCustomProperties());
+        self::assertTrue($object->isCustomPropertySet('pName'));
+        self::assertEquals(DocumentProperties::PROPERTY_TYPE_STRING, $object->getCustomPropertyType('pName'));
+        self::assertNull($object->getCustomPropertyValue('pName'));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', $valueTime, DocumentProperties::PROPERTY_TYPE_DATE));
+        self::assertCount(1, $object->getCustomProperties());
+        self::assertTrue($object->isCustomPropertySet('pName'));
+        self::assertEquals(DocumentProperties::PROPERTY_TYPE_DATE, $object->getCustomPropertyType('pName'));
+        self::assertEquals($valueTime, $object->getCustomPropertyValue('pName'));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->setCustomProperty('pName', (string) $valueTime, DocumentProperties::PROPERTY_TYPE_UNKNOWN));
+        self::assertCount(1, $object->getCustomProperties());
+        self::assertTrue($object->isCustomPropertySet('pName'));
+        self::assertEquals(DocumentProperties::PROPERTY_TYPE_STRING, $object->getCustomPropertyType('pName'));
+        self::assertEquals($valueTime, $object->getCustomPropertyValue('pName'));
     }
 }
diff --git a/tests/PhpPresentation/Tests/HashTableTest.php b/tests/PhpPresentation/Tests/HashTableTest.php
index 18c3a149a5..e6503135c6 100644
--- a/tests/PhpPresentation/Tests/HashTableTest.php
+++ b/tests/PhpPresentation/Tests/HashTableTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,11 +34,11 @@ public function testConstructNull(): void
     {
         $object = new HashTable();
 
-        $this->assertEquals(0, $object->count());
-        $this->assertNull($object->getByIndex());
-        $this->assertNull($object->getByHashCode());
-        $this->assertIsArray($object->toArray());
-        $this->assertEmpty($object->toArray());
+        self::assertEquals(0, $object->count());
+        self::assertNull($object->getByIndex());
+        self::assertNull($object->getByHashCode());
+        self::assertIsArray($object->toArray());
+        self::assertEmpty($object->toArray());
     }
 
     public function testConstructSource(): void
@@ -49,9 +48,9 @@ public function testConstructSource(): void
             new Slide(),
         ]);
 
-        $this->assertEquals(2, $object->count());
-        $this->assertIsArray($object->toArray());
-        $this->assertCount(2, $object->toArray());
+        self::assertEquals(2, $object->count());
+        self::assertIsArray($object->toArray());
+        self::assertCount(2, $object->toArray());
     }
 
     public function testAdd(): void
@@ -63,22 +62,22 @@ public function testAdd(): void
         $object->addFromSource();
         // Add From Source : Array
         $object->addFromSource([$oSlide]);
-        $this->assertIsArray($object->toArray());
-        $this->assertCount(1, $object->toArray());
+        self::assertIsArray($object->toArray());
+        self::assertCount(1, $object->toArray());
         // Clear
         $object->clear();
-        $this->assertEmpty($object->toArray());
+        self::assertEmpty($object->toArray());
         // Add Object
         $object->add($oSlide);
-        $this->assertCount(1, $object->toArray());
+        self::assertCount(1, $object->toArray());
         $object->clear();
         // Add Object w/Hash Index
-        $oSlide->setHashIndex(rand(1, 100));
+        $oSlide->setHashIndex(mt_rand(1, 100));
         $object->add($oSlide);
-        $this->assertCount(1, $object->toArray());
+        self::assertCount(1, $object->toArray());
         // Add Object w/the same Hash Index
         $object->add($oSlide);
-        $this->assertCount(1, $object->toArray());
+        self::assertCount(1, $object->toArray());
     }
 
     public function testIndex(): void
@@ -91,10 +90,10 @@ public function testIndex(): void
         $object->add($oSlide1);
         $object->add($oSlide2);
         // Index
-        $this->assertEquals(0, $object->getIndexForHashCode($oSlide1->getHashCode()));
-        $this->assertEquals(1, $object->getIndexForHashCode($oSlide2->getHashCode()));
-        $this->assertEquals($oSlide1, $object->getByIndex(0));
-        $this->assertEquals($oSlide2, $object->getByIndex(1));
+        self::assertEquals(0, $object->getIndexForHashCode($oSlide1->getHashCode()));
+        self::assertEquals(1, $object->getIndexForHashCode($oSlide2->getHashCode()));
+        self::assertEquals($oSlide1, $object->getByIndex(0));
+        self::assertEquals($oSlide2, $object->getByIndex(1));
     }
 
     public function testRemove(): void
@@ -110,8 +109,8 @@ public function testRemove(): void
         $object->add($oSlide3);
         // Remove
         $object->remove($oSlide2);
-        $this->assertCount(2, $object->toArray());
+        self::assertCount(2, $object->toArray());
         $object->remove($oSlide3);
-        $this->assertCount(1, $object->toArray());
+        self::assertCount(1, $object->toArray());
     }
 }
diff --git a/tests/PhpPresentation/Tests/IOFactoryTest.php b/tests/PhpPresentation/Tests/IOFactoryTest.php
index d17f615482..504890891f 100644
--- a/tests/PhpPresentation/Tests/IOFactoryTest.php
+++ b/tests/PhpPresentation/Tests/IOFactoryTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -40,7 +39,7 @@ public function testCreateWriter(): void
     {
         $class = 'PhpOffice\\PhpPresentation\\Writer\\PowerPoint2007';
 
-        $this->assertInstanceOf($class, IOFactory::createWriter(new PhpPresentation()));
+        self::assertInstanceOf($class, IOFactory::createWriter(new PhpPresentation()));
     }
 
     /**
@@ -50,7 +49,7 @@ public function testCreateReader(): void
     {
         $class = 'PhpOffice\\PhpPresentation\\Reader\\ReaderInterface';
 
-        $this->assertInstanceOf($class, IOFactory::createReader('Serialized'));
+        self::assertInstanceOf($class, IOFactory::createReader('Serialized'));
     }
 
     /**
@@ -65,7 +64,7 @@ public function testLoadClassException(): void
 
     public function testLoad(): void
     {
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', IOFactory::load(PHPPRESENTATION_TESTS_BASE_DIR . DIRECTORY_SEPARATOR . 'resources' . DIRECTORY_SEPARATOR . 'files' . DIRECTORY_SEPARATOR . 'serialized.phppt'));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', IOFactory::load(PHPPRESENTATION_TESTS_BASE_DIR . DIRECTORY_SEPARATOR . 'resources' . DIRECTORY_SEPARATOR . 'files' . DIRECTORY_SEPARATOR . 'serialized.phppt'));
     }
 
     /**
diff --git a/tests/PhpPresentation/Tests/PhpPresentationTest.php b/tests/PhpPresentation/Tests/PhpPresentationTest.php
index 3370f92460..a093e6b023 100644
--- a/tests/PhpPresentation/Tests/PhpPresentationTest.php
+++ b/tests/PhpPresentation/Tests/PhpPresentationTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -42,30 +41,30 @@ public function testConstruct(): void
         $object = new PhpPresentation();
         $slide = $object->getSlide();
 
-        $this->assertEquals(new DocumentProperties(), $object->getDocumentProperties());
-        $this->assertEquals(new DocumentLayout(), $object->getLayout());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide', $object->getSlide());
-        $this->assertCount(1, $object->getAllSlides());
-        $this->assertEquals(0, $object->getIndex($slide));
-        $this->assertEquals(1, $object->getSlideCount());
-        $this->assertEquals(0, $object->getActiveSlideIndex());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Iterator', $object->getSlideIterator());
+        self::assertEquals(new DocumentProperties(), $object->getDocumentProperties());
+        self::assertEquals(new DocumentLayout(), $object->getLayout());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide', $object->getSlide());
+        self::assertCount(1, $object->getAllSlides());
+        self::assertEquals(0, $object->getIndex($slide));
+        self::assertEquals(1, $object->getSlideCount());
+        self::assertEquals(0, $object->getActiveSlideIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Iterator', $object->getSlideIterator());
     }
 
     public function testProperties(): void
     {
         $object = new PhpPresentation();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->getDocumentProperties());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->setDocumentProperties(new DocumentProperties()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->getDocumentProperties());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->getDocumentProperties());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->setDocumentProperties(new DocumentProperties()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\DocumentProperties', $object->getDocumentProperties());
     }
 
     public function testPresentationProperties(): void
     {
         $object = new PhpPresentation();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PresentationProperties', $object->getPresentationProperties());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->setPresentationProperties(new PresentationProperties()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PresentationProperties', $object->getPresentationProperties());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PresentationProperties', $object->getPresentationProperties());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->setPresentationProperties(new PresentationProperties()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PresentationProperties', $object->getPresentationProperties());
     }
 
     /**
@@ -78,7 +77,7 @@ public function testAddExternalSlide(): void
         $object = new PhpPresentation();
         $object->addExternalSlide($slide);
 
-        $this->assertEquals(2, $object->getSlideCount());
+        self::assertEquals(2, $object->getSlideCount());
     }
 
     /**
@@ -87,7 +86,7 @@ public function testAddExternalSlide(): void
     public function testCopy(): void
     {
         $object = new PhpPresentation();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->copy());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->copy());
     }
 
     /**
diff --git a/tests/PhpPresentation/Tests/PresentationPropertiesTest.php b/tests/PhpPresentation/Tests/PresentationPropertiesTest.php
index 56d88f5d4a..aaa7c74b02 100644
--- a/tests/PhpPresentation/Tests/PresentationPropertiesTest.php
+++ b/tests/PhpPresentation/Tests/PresentationPropertiesTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -33,49 +32,49 @@ class PresentationPropertiesTest extends TestCase
     public function testCommentVisible(): void
     {
         $object = new PresentationProperties();
-        $this->assertFalse($object->isCommentVisible());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setCommentVisible(true));
-        $this->assertTrue($object->isCommentVisible());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setCommentVisible(false));
-        $this->assertFalse($object->isCommentVisible());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setCommentVisible());
-        $this->assertFalse($object->isCommentVisible());
+        self::assertFalse($object->isCommentVisible());
+        self::assertInstanceOf(PresentationProperties::class, $object->setCommentVisible(true));
+        self::assertTrue($object->isCommentVisible());
+        self::assertInstanceOf(PresentationProperties::class, $object->setCommentVisible(false));
+        self::assertFalse($object->isCommentVisible());
+        self::assertInstanceOf(PresentationProperties::class, $object->setCommentVisible());
+        self::assertFalse($object->isCommentVisible());
     }
 
     public function testLoopUntilEsc(): void
     {
         $object = new PresentationProperties();
-        $this->assertFalse($object->isLoopContinuouslyUntilEsc());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setLoopContinuouslyUntilEsc(true));
-        $this->assertTrue($object->isLoopContinuouslyUntilEsc());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setLoopContinuouslyUntilEsc(false));
-        $this->assertFalse($object->isLoopContinuouslyUntilEsc());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setLoopContinuouslyUntilEsc());
-        $this->assertFalse($object->isLoopContinuouslyUntilEsc());
+        self::assertFalse($object->isLoopContinuouslyUntilEsc());
+        self::assertInstanceOf(PresentationProperties::class, $object->setLoopContinuouslyUntilEsc(true));
+        self::assertTrue($object->isLoopContinuouslyUntilEsc());
+        self::assertInstanceOf(PresentationProperties::class, $object->setLoopContinuouslyUntilEsc(false));
+        self::assertFalse($object->isLoopContinuouslyUntilEsc());
+        self::assertInstanceOf(PresentationProperties::class, $object->setLoopContinuouslyUntilEsc());
+        self::assertFalse($object->isLoopContinuouslyUntilEsc());
     }
 
     public function testLastView(): void
     {
         $object = new PresentationProperties();
-        $this->assertEquals(PresentationProperties::VIEW_SLIDE, $object->getLastView());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setLastView('AAAA'));
-        $this->assertEquals(PresentationProperties::VIEW_SLIDE, $object->getLastView());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setLastView(PresentationProperties::VIEW_OUTLINE));
-        $this->assertEquals(PresentationProperties::VIEW_OUTLINE, $object->getLastView());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setLastView());
-        $this->assertEquals(PresentationProperties::VIEW_SLIDE, $object->getLastView());
+        self::assertEquals(PresentationProperties::VIEW_SLIDE, $object->getLastView());
+        self::assertInstanceOf(PresentationProperties::class, $object->setLastView('AAAA'));
+        self::assertEquals(PresentationProperties::VIEW_SLIDE, $object->getLastView());
+        self::assertInstanceOf(PresentationProperties::class, $object->setLastView(PresentationProperties::VIEW_OUTLINE));
+        self::assertEquals(PresentationProperties::VIEW_OUTLINE, $object->getLastView());
+        self::assertInstanceOf(PresentationProperties::class, $object->setLastView());
+        self::assertEquals(PresentationProperties::VIEW_SLIDE, $object->getLastView());
     }
 
     public function testMarkAsFinal(): void
     {
         $object = new PresentationProperties();
-        $this->assertFalse($object->isMarkedAsFinal());
-        $this->assertInstanceOf(PresentationProperties::class, $object->markAsFinal(true));
-        $this->assertTrue($object->isMarkedAsFinal());
-        $this->assertInstanceOf(PresentationProperties::class, $object->markAsFinal(false));
-        $this->assertFalse($object->isMarkedAsFinal());
-        $this->assertInstanceOf(PresentationProperties::class, $object->markAsFinal());
-        $this->assertTrue($object->isMarkedAsFinal());
+        self::assertFalse($object->isMarkedAsFinal());
+        self::assertInstanceOf(PresentationProperties::class, $object->markAsFinal(true));
+        self::assertTrue($object->isMarkedAsFinal());
+        self::assertInstanceOf(PresentationProperties::class, $object->markAsFinal(false));
+        self::assertFalse($object->isMarkedAsFinal());
+        self::assertInstanceOf(PresentationProperties::class, $object->markAsFinal());
+        self::assertTrue($object->isMarkedAsFinal());
     }
 
     /**
@@ -85,19 +84,19 @@ public function testSlideshowType(?string $value, string $expected): void
     {
         $object = new PresentationProperties();
         // Default
-        $this->assertEquals(PresentationProperties::SLIDESHOW_TYPE_PRESENT, $object->getSlideshowType());
+        self::assertEquals(PresentationProperties::SLIDESHOW_TYPE_PRESENT, $object->getSlideshowType());
         // Set value
-        if (is_null($value)) {
-            $this->assertInstanceOf(PresentationProperties::class, $object->setSlideshowType());
+        if (null === $value) {
+            self::assertInstanceOf(PresentationProperties::class, $object->setSlideshowType());
         } else {
-            $this->assertInstanceOf(PresentationProperties::class, $object->setSlideshowType($value));
+            self::assertInstanceOf(PresentationProperties::class, $object->setSlideshowType($value));
         }
         // Check value
-        $this->assertEquals($expected, $object->getSlideshowType());
+        self::assertEquals($expected, $object->getSlideshowType());
     }
 
     /**
-     * @return array<array<string|null>>
+     * @return array<array<null|string>>
      */
     public function dataProviderSlideshowType(): array
     {
@@ -130,24 +129,24 @@ public function testThumbnail(): void
         $imagePath = PHPPRESENTATION_TESTS_BASE_DIR . DIRECTORY_SEPARATOR . 'resources' . DIRECTORY_SEPARATOR . 'images' . DIRECTORY_SEPARATOR . 'PhpPresentationLogo.png';
 
         $object = new PresentationProperties();
-        $this->assertNull($object->getThumbnailPath());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setThumbnailPath('AAAA'));
-        $this->assertNull($object->getThumbnailPath());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setThumbnailPath());
-        $this->assertNull($object->getThumbnailPath());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setThumbnailPath($imagePath));
-        $this->assertEquals($imagePath, $object->getThumbnailPath());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setThumbnailPath());
-        $this->assertEquals($imagePath, $object->getThumbnailPath());
+        self::assertNull($object->getThumbnailPath());
+        self::assertInstanceOf(PresentationProperties::class, $object->setThumbnailPath('AAAA'));
+        self::assertNull($object->getThumbnailPath());
+        self::assertInstanceOf(PresentationProperties::class, $object->setThumbnailPath());
+        self::assertNull($object->getThumbnailPath());
+        self::assertInstanceOf(PresentationProperties::class, $object->setThumbnailPath($imagePath));
+        self::assertEquals($imagePath, $object->getThumbnailPath());
+        self::assertInstanceOf(PresentationProperties::class, $object->setThumbnailPath());
+        self::assertEquals($imagePath, $object->getThumbnailPath());
     }
 
     public function testZoom(): void
     {
         $object = new PresentationProperties();
-        $this->assertEquals(1, $object->getZoom());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setZoom(2.3));
-        $this->assertEquals(2.3, $object->getZoom());
-        $this->assertInstanceOf(PresentationProperties::class, $object->setZoom());
-        $this->assertEquals(1, $object->getZoom());
+        self::assertEquals(1, $object->getZoom());
+        self::assertInstanceOf(PresentationProperties::class, $object->setZoom(2.3));
+        self::assertEquals(2.3, $object->getZoom());
+        self::assertInstanceOf(PresentationProperties::class, $object->setZoom());
+        self::assertEquals(1, $object->getZoom());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Reader/ODPresentationTest.php b/tests/PhpPresentation/Tests/Reader/ODPresentationTest.php
index 418215bbf5..62fb2d0e71 100644
--- a/tests/PhpPresentation/Tests/Reader/ODPresentationTest.php
+++ b/tests/PhpPresentation/Tests/Reader/ODPresentationTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -47,16 +46,16 @@ public function testCanRead(): void
         $object = new ODPresentation();
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_00_01.ppt';
-        $this->assertFalse($object->canRead($file));
+        self::assertFalse($object->canRead($file));
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/serialized.phppt';
-        $this->assertFalse($object->canRead($file));
+        self::assertFalse($object->canRead($file));
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_12.pptx';
-        $this->assertFalse($object->canRead($file));
+        self::assertFalse($object->canRead($file));
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_12.odp';
-        $this->assertTrue($object->canRead($file));
+        self::assertTrue($object->canRead($file));
     }
 
     public function testLoadFileNotExists(): void
@@ -95,475 +94,475 @@ public function testLoadFile01(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_12.odp';
         $object = new ODPresentation();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
         // Document Properties
-        $this->assertEquals('PHPOffice', $oPhpPresentation->getDocumentProperties()->getCreator());
-        $this->assertEquals('PHPPresentation Team', $oPhpPresentation->getDocumentProperties()->getLastModifiedBy());
-        $this->assertEquals('Sample 02 Title', $oPhpPresentation->getDocumentProperties()->getTitle());
-        $this->assertEquals('Sample 02 Subject', $oPhpPresentation->getDocumentProperties()->getSubject());
-        $this->assertEquals('Sample 02 Description', $oPhpPresentation->getDocumentProperties()->getDescription());
-        $this->assertEquals('office 2007 openxml libreoffice odt php', $oPhpPresentation->getDocumentProperties()->getKeywords());
-        $this->assertIsArray($oPhpPresentation->getDocumentProperties()->getCustomProperties());
-        $this->assertCount(0, $oPhpPresentation->getDocumentProperties()->getCustomProperties());
+        self::assertEquals('PHPOffice', $oPhpPresentation->getDocumentProperties()->getCreator());
+        self::assertEquals('PHPPresentation Team', $oPhpPresentation->getDocumentProperties()->getLastModifiedBy());
+        self::assertEquals('Sample 02 Title', $oPhpPresentation->getDocumentProperties()->getTitle());
+        self::assertEquals('Sample 02 Subject', $oPhpPresentation->getDocumentProperties()->getSubject());
+        self::assertEquals('Sample 02 Description', $oPhpPresentation->getDocumentProperties()->getDescription());
+        self::assertEquals('office 2007 openxml libreoffice odt php', $oPhpPresentation->getDocumentProperties()->getKeywords());
+        self::assertIsArray($oPhpPresentation->getDocumentProperties()->getCustomProperties());
+        self::assertCount(0, $oPhpPresentation->getDocumentProperties()->getCustomProperties());
 
         // Presentation Properties
-        $this->assertEquals(PresentationProperties::SLIDESHOW_TYPE_PRESENT, $oPhpPresentation->getPresentationProperties()->getSlideshowType());
+        self::assertEquals(PresentationProperties::SLIDESHOW_TYPE_PRESENT, $oPhpPresentation->getPresentationProperties()->getSlideshowType());
 
-        $this->assertCount(4, $oPhpPresentation->getAllSlides());
+        self::assertCount(4, $oPhpPresentation->getAllSlides());
 
         // Slide 1
         $oSlide1 = $oPhpPresentation->getSlide(0);
         $arrayShape = (array) $oSlide1->getShapeCollection();
-        $this->assertCount(2, $arrayShape);
+        self::assertCount(2, $arrayShape);
         // Slide 1 : Shape 1
         /** @var Gd $oShape */
         $oShape = $arrayShape[0];
-        $this->assertInstanceOf(Gd::class, $oShape);
-        $this->assertEquals('PHPPresentation logo', $oShape->getName());
-        $this->assertEquals('PHPPresentation logo', $oShape->getDescription());
-        $this->assertEquals(36, $oShape->getHeight());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(10, $oShape->getOffsetY());
-        $this->assertEquals('image/png', $oShape->getMimeType());
-        $this->assertTrue($oShape->getShadow()->isVisible());
-        $this->assertEquals(45, $oShape->getShadow()->getDirection());
-        $this->assertEquals(10, $oShape->getShadow()->getDistance());
+        self::assertInstanceOf(Gd::class, $oShape);
+        self::assertEquals('PHPPresentation logo', $oShape->getName());
+        self::assertEquals('PHPPresentation logo', $oShape->getDescription());
+        self::assertEquals(36, $oShape->getHeight());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(10, $oShape->getOffsetY());
+        self::assertEquals('image/png', $oShape->getMimeType());
+        self::assertTrue($oShape->getShadow()->isVisible());
+        self::assertEquals(45, $oShape->getShadow()->getDirection());
+        self::assertEquals(10, $oShape->getShadow()->getDistance());
         // Slide 1 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[1];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(200, $oShape->getHeight());
-        $this->assertEquals(600, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(400, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(200, $oShape->getHeight());
+        self::assertEquals(600, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(400, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $oParagraph);
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
-        $this->assertEquals(0, $oParagraph->getSpacingAfter());
-        $this->assertEquals(0, $oParagraph->getSpacingBefore());
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
-        $this->assertEquals(100, $oParagraph->getLineSpacing());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $oParagraph);
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(0, $oParagraph->getSpacingAfter());
+        self::assertEquals(0, $oParagraph->getSpacingBefore());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
+        self::assertEquals(100, $oParagraph->getLineSpacing());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(3, $arrayRichText);
+        self::assertCount(3, $arrayRichText);
         // Slide 1 : Shape 2 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Introduction to', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(28, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Introduction to', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(28, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 1 : Shape 2 : Paragraph 2
         $oRichText = $arrayRichText[1];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $oRichText);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $oRichText);
         // Slide 1 : Shape 2 : Paragraph 3
         $oRichText = $arrayRichText[2];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('PHPPresentation', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(60, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('PHPPresentation', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(60, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
 
         // Slide 2
         $oSlide2 = $oPhpPresentation->getSlide(1);
         $arrayShape = (array) $oSlide2->getShapeCollection();
-        $this->assertCount(3, $arrayShape);
+        self::assertCount(3, $arrayShape);
         // Slide 2 : Shape 1
         /** @var Gd $oShape */
         $oShape = $arrayShape[0];
-        $this->assertInstanceOf(Gd::class, $oShape);
-        $this->assertEquals('PHPPresentation logo', $oShape->getName());
-        $this->assertEquals('PHPPresentation logo', $oShape->getDescription());
-        $this->assertEquals(36, $oShape->getHeight());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(10, $oShape->getOffsetY());
-        $this->assertEquals('image/png', $oShape->getMimeType());
-        $this->assertTrue($oShape->getShadow()->isVisible());
-        $this->assertEquals(45, $oShape->getShadow()->getDirection());
-        $this->assertEquals(10, $oShape->getShadow()->getDistance());
+        self::assertInstanceOf(Gd::class, $oShape);
+        self::assertEquals('PHPPresentation logo', $oShape->getName());
+        self::assertEquals('PHPPresentation logo', $oShape->getDescription());
+        self::assertEquals(36, $oShape->getHeight());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(10, $oShape->getOffsetY());
+        self::assertEquals('image/png', $oShape->getMimeType());
+        self::assertTrue($oShape->getShadow()->isVisible());
+        self::assertEquals(45, $oShape->getShadow()->getDirection());
+        self::assertEquals(10, $oShape->getShadow()->getDistance());
         // Slide 2 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[1];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(100, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(50, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(100, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(50, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         // Slide 2 : Shape 2 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('What is PHPPresentation?', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(48, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('What is PHPPresentation?', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(48, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
         // Slide 2 : Shape 3
         /** @var RichText $oShape */
         $oShape = $arrayShape[2];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(600, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(130, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(600, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(130, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(4, $arrayParagraphs);
+        self::assertCount(4, $arrayParagraphs);
         // Slide 2 : Shape 3 : Paragraph 1
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('A class library', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('A class library', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 2 : Shape 3 : Paragraph 2
         $oParagraph = $arrayParagraphs[1];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Written in PHP', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Written in PHP', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 2 : Shape 3 : Paragraph 3
         $oParagraph = $arrayParagraphs[2];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Representing a presentation', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Representing a presentation', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 2 : Shape 3 : Paragraph 4
         $oParagraph = $arrayParagraphs[3];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Supports writing to different file formats', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Supports writing to different file formats', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
 
         // Slide 3
         $oSlide2 = $oPhpPresentation->getSlide(2);
         $arrayShape = (array) $oSlide2->getShapeCollection();
-        $this->assertCount(3, $arrayShape);
+        self::assertCount(3, $arrayShape);
         // Slide 3 : Shape 1
         /** @var Gd $oShape */
         $oShape = $arrayShape[0];
-        $this->assertInstanceOf(Gd::class, $oShape);
-        $this->assertEquals('PHPPresentation logo', $oShape->getName());
-        $this->assertEquals('PHPPresentation logo', $oShape->getDescription());
-        $this->assertEquals(36, $oShape->getHeight());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(10, $oShape->getOffsetY());
-        $this->assertEquals('image/png', $oShape->getMimeType());
-        $this->assertTrue($oShape->getShadow()->isVisible());
-        $this->assertEquals(45, $oShape->getShadow()->getDirection());
-        $this->assertEquals(10, $oShape->getShadow()->getDistance());
+        self::assertInstanceOf(Gd::class, $oShape);
+        self::assertEquals('PHPPresentation logo', $oShape->getName());
+        self::assertEquals('PHPPresentation logo', $oShape->getDescription());
+        self::assertEquals(36, $oShape->getHeight());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(10, $oShape->getOffsetY());
+        self::assertEquals('image/png', $oShape->getMimeType());
+        self::assertTrue($oShape->getShadow()->isVisible());
+        self::assertEquals(45, $oShape->getShadow()->getDirection());
+        self::assertEquals(10, $oShape->getShadow()->getDistance());
         // Slide 3 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[1];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(100, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(50, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(100, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(50, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
-        $this->assertEquals(0, $oParagraph->getSpacingAfter());
-        $this->assertEquals(0, $oParagraph->getSpacingBefore());
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
-        $this->assertEquals(100, $oParagraph->getLineSpacing());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(0, $oParagraph->getSpacingAfter());
+        self::assertEquals(0, $oParagraph->getSpacingBefore());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
+        self::assertEquals(100, $oParagraph->getLineSpacing());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         // Slide 3 : Shape 2 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('What\'s the point?', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(48, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('What\'s the point?', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(48, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[2];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(600, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(130, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(600, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(130, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(8, $arrayParagraphs);
+        self::assertCount(8, $arrayParagraphs);
         // Slide 3 : Shape 3 : Paragraph 1
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(0, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(0, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Generate slide decks', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Generate slide decks', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 2
         $oParagraph = $arrayParagraphs[1];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Represent business data', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Represent business data', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 3
         $oParagraph = $arrayParagraphs[2];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Show a family slide show', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Show a family slide show', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 4
         $oParagraph = $arrayParagraphs[3];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('...', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('...', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 5
         $oParagraph = $arrayParagraphs[4];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(0, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(0, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Export these to different formats', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Export these to different formats', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 6
         $oParagraph = $arrayParagraphs[5];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('PHPPresentation 2007', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('PHPPresentation 2007', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 7
         $oParagraph = $arrayParagraphs[6];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Serialized', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Serialized', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 8
         $oParagraph = $arrayParagraphs[7];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
 //         $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
 //         $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('... (more to come) ...', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('... (more to come) ...', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
 
         // Slide 4
         $oSlide3 = $oPhpPresentation->getSlide(3);
         $arrayShape = (array) $oSlide3->getShapeCollection();
-        $this->assertCount(3, $arrayShape);
+        self::assertCount(3, $arrayShape);
         // Slide 4 : Shape 1
         /** @var Gd $oShape */
         $oShape = $arrayShape[0];
-        $this->assertInstanceOf(Gd::class, $oShape);
-        $this->assertEquals('PHPPresentation logo', $oShape->getName());
-        $this->assertEquals('PHPPresentation logo', $oShape->getDescription());
-        $this->assertEquals(36, $oShape->getHeight());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(10, $oShape->getOffsetY());
-        $this->assertEquals('image/png', $oShape->getMimeType());
-        $this->assertTrue($oShape->getShadow()->isVisible());
-        $this->assertEquals(45, $oShape->getShadow()->getDirection());
-        $this->assertEquals(10, $oShape->getShadow()->getDistance());
+        self::assertInstanceOf(Gd::class, $oShape);
+        self::assertEquals('PHPPresentation logo', $oShape->getName());
+        self::assertEquals('PHPPresentation logo', $oShape->getDescription());
+        self::assertEquals(36, $oShape->getHeight());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(10, $oShape->getOffsetY());
+        self::assertEquals('image/png', $oShape->getMimeType());
+        self::assertTrue($oShape->getShadow()->isVisible());
+        self::assertEquals(45, $oShape->getShadow()->getDirection());
+        self::assertEquals(10, $oShape->getShadow()->getDistance());
         // Slide 4 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[1];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(100, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(50, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(100, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(50, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
-        $this->assertEquals(0, $oParagraph->getSpacingAfter());
-        $this->assertEquals(0, $oParagraph->getSpacingBefore());
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
-        $this->assertEquals(100, $oParagraph->getLineSpacing());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(0, $oParagraph->getSpacingAfter());
+        self::assertEquals(0, $oParagraph->getSpacingBefore());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
+        self::assertEquals(100, $oParagraph->getLineSpacing());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         // Slide 4 : Shape 2 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Need more info?', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(48, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Need more info?', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(48, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 4 : Shape 3
         /** @var RichText $oShape */
         $oShape = $arrayShape[2];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(600, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(130, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(600, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(130, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
-        $this->assertEquals(0, $oParagraph->getSpacingAfter());
-        $this->assertEquals(0, $oParagraph->getSpacingBefore());
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
-        $this->assertEquals(100, $oParagraph->getLineSpacing());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(0, $oParagraph->getSpacingAfter());
+        self::assertEquals(0, $oParagraph->getSpacingBefore());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
+        self::assertEquals(100, $oParagraph->getLineSpacing());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(3, $arrayRichText);
+        self::assertCount(3, $arrayRichText);
         // Slide 4 : Shape 3 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Check the project site on GitHub:', $oRichText->getText());
-        $this->assertFalse($oRichText->getFont()->isBold());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Check the project site on GitHub:', $oRichText->getText());
+        self::assertFalse($oRichText->getFont()->isBold());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 4 : Shape 3 : Paragraph 2
         $oRichText = $arrayRichText[1];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $oRichText);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $oRichText);
         // Slide 4 : Shape 3 : Paragraph 3
         /** @var RichText\Run $oRichText */
         $oRichText = $arrayRichText[2];
-        $this->assertInstanceOf(RichText\Run::class, $oRichText);
-        $this->assertEquals('https://github.com/PHPOffice/PHPPresentation/', $oRichText->getText());
-        $this->assertFalse($oRichText->getFont()->isBold());
-        $this->assertEquals(32, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
-        $this->assertTrue($oRichText->hasHyperlink());
-        $this->assertEquals('https://github.com/PHPOffice/PHPPresentation/', $oRichText->getHyperlink()->getUrl());
+        self::assertInstanceOf(RichText\Run::class, $oRichText);
+        self::assertEquals('https://github.com/PHPOffice/PHPPresentation/', $oRichText->getText());
+        self::assertFalse($oRichText->getFont()->isBold());
+        self::assertEquals(32, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertTrue($oRichText->hasHyperlink());
+        self::assertEquals('https://github.com/PHPOffice/PHPPresentation/', $oRichText->getHyperlink()->getUrl());
         //$this->assertEquals('PHPPresentation', $oRichText->getHyperlink()->getTooltip());
     }
 
@@ -572,11 +571,11 @@ public function testSlideName(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/ODP_Slide_Name.odp';
         $object = new ODPresentation();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertIsArray($oPhpPresentation->getDocumentProperties()->getCustomProperties());
-        $this->assertCount(0, $oPhpPresentation->getDocumentProperties()->getCustomProperties());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertIsArray($oPhpPresentation->getDocumentProperties()->getCustomProperties());
+        self::assertCount(0, $oPhpPresentation->getDocumentProperties()->getCustomProperties());
 
-        $this->assertEquals('MaDiapo', $oPhpPresentation->getSlide(0)->getName());
+        self::assertEquals('MaDiapo', $oPhpPresentation->getSlide(0)->getName());
     }
 
     public function testIssue00141(): void
@@ -584,28 +583,28 @@ public function testIssue00141(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Issue_00141.odp';
         $object = new ODPresentation();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertIsArray($oPhpPresentation->getDocumentProperties()->getCustomProperties());
-        $this->assertCount(0, $oPhpPresentation->getDocumentProperties()->getCustomProperties());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertIsArray($oPhpPresentation->getDocumentProperties()->getCustomProperties());
+        self::assertCount(0, $oPhpPresentation->getDocumentProperties()->getCustomProperties());
 
-        $this->assertCount(3, $oPhpPresentation->getAllSlides());
+        self::assertCount(3, $oPhpPresentation->getAllSlides());
 
         // Slide 1
         $oSlide = $oPhpPresentation->getSlide(1);
         $arrayShape = (array) $oSlide->getShapeCollection();
-        $this->assertCount(2, $arrayShape);
+        self::assertCount(2, $arrayShape);
         // Slide 1 : Shape 1
         /** @var RichText $oShape */
         $oShape = reset($arrayShape);
-        $this->assertInstanceOf(RichText::class, $oShape);
+        self::assertInstanceOf(RichText::class, $oShape);
         // Slide 1 : Shape 1 : Paragraph 1
         $oParagraph = $oShape->getParagraph();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $oParagraph);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $oParagraph);
         // Slide 1 : Shape 1 : Paragraph 1 : RichText Elements
         $arrayElements = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayElements);
+        self::assertCount(1, $arrayElements);
         $oElement = reset($arrayElements);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $oElement);
-        $this->assertEquals('TEST IMAGE', $oElement->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $oElement);
+        self::assertEquals('TEST IMAGE', $oElement->getText());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Reader/PowerPoint2007Test.php b/tests/PhpPresentation/Tests/Reader/PowerPoint2007Test.php
index dea2f75373..f90b7e7887 100644
--- a/tests/PhpPresentation/Tests/Reader/PowerPoint2007Test.php
+++ b/tests/PhpPresentation/Tests/Reader/PowerPoint2007Test.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -48,13 +47,13 @@ public function testCanRead(): void
         $object = new PowerPoint2007();
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_00_01.ppt';
-        $this->assertFalse($object->canRead($file));
+        self::assertFalse($object->canRead($file));
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/serialized.phppt';
-        $this->assertFalse($object->canRead($file));
+        self::assertFalse($object->canRead($file));
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_12.pptx';
-        $this->assertTrue($object->canRead($file));
+        self::assertTrue($object->canRead($file));
     }
 
     public function testLoadFileNotExists(): void
@@ -93,484 +92,484 @@ public function testLoadFile01(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_12.pptx';
         $object = new PowerPoint2007();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
         // Document Properties
-        $this->assertEquals('PHPOffice', $oPhpPresentation->getDocumentProperties()->getCreator());
-        $this->assertEquals('PHPPresentation Team', $oPhpPresentation->getDocumentProperties()->getLastModifiedBy());
-        $this->assertEquals('Sample 02 Title', $oPhpPresentation->getDocumentProperties()->getTitle());
-        $this->assertEquals('Sample 02 Subject', $oPhpPresentation->getDocumentProperties()->getSubject());
-        $this->assertEquals('Sample 02 Description', $oPhpPresentation->getDocumentProperties()->getDescription());
-        $this->assertEquals('office 2007 openxml libreoffice odt php', $oPhpPresentation->getDocumentProperties()->getKeywords());
-        $this->assertEquals('Sample Category', $oPhpPresentation->getDocumentProperties()->getCategory());
-        $this->assertIsArray($oPhpPresentation->getDocumentProperties()->getCustomProperties());
-        $this->assertCount(0, $oPhpPresentation->getDocumentProperties()->getCustomProperties());
+        self::assertEquals('PHPOffice', $oPhpPresentation->getDocumentProperties()->getCreator());
+        self::assertEquals('PHPPresentation Team', $oPhpPresentation->getDocumentProperties()->getLastModifiedBy());
+        self::assertEquals('Sample 02 Title', $oPhpPresentation->getDocumentProperties()->getTitle());
+        self::assertEquals('Sample 02 Subject', $oPhpPresentation->getDocumentProperties()->getSubject());
+        self::assertEquals('Sample 02 Description', $oPhpPresentation->getDocumentProperties()->getDescription());
+        self::assertEquals('office 2007 openxml libreoffice odt php', $oPhpPresentation->getDocumentProperties()->getKeywords());
+        self::assertEquals('Sample Category', $oPhpPresentation->getDocumentProperties()->getCategory());
+        self::assertIsArray($oPhpPresentation->getDocumentProperties()->getCustomProperties());
+        self::assertCount(0, $oPhpPresentation->getDocumentProperties()->getCustomProperties());
 
         // Presentation Properties
-        $this->assertEquals(PresentationProperties::SLIDESHOW_TYPE_PRESENT, $oPhpPresentation->getPresentationProperties()->getSlideshowType());
+        self::assertEquals(PresentationProperties::SLIDESHOW_TYPE_PRESENT, $oPhpPresentation->getPresentationProperties()->getSlideshowType());
         // Document Layout
-        $this->assertEquals(DocumentLayout::LAYOUT_SCREEN_4X3, $oPhpPresentation->getLayout()->getDocumentLayout());
-        $this->assertEquals(254, $oPhpPresentation->getLayout()->getCX(DocumentLayout::UNIT_MILLIMETER));
-        $this->assertEquals(190.5, $oPhpPresentation->getLayout()->getCY(DocumentLayout::UNIT_MILLIMETER));
+        self::assertEquals(DocumentLayout::LAYOUT_SCREEN_4X3, $oPhpPresentation->getLayout()->getDocumentLayout());
+        self::assertEquals(254, $oPhpPresentation->getLayout()->getCX(DocumentLayout::UNIT_MILLIMETER));
+        self::assertEquals(190.5, $oPhpPresentation->getLayout()->getCY(DocumentLayout::UNIT_MILLIMETER));
 
         // Slides
-        $this->assertCount(4, $oPhpPresentation->getAllSlides());
+        self::assertCount(4, $oPhpPresentation->getAllSlides());
 
         // Slide 1
         $oSlide1 = $oPhpPresentation->getSlide(0);
         $arrayShape = (array) $oSlide1->getShapeCollection();
-        $this->assertCount(2, $arrayShape);
+        self::assertCount(2, $arrayShape);
         // Slide 1 : Shape 1
         /** @var Gd $oShape */
         $oShape = $arrayShape[0];
-        $this->assertInstanceOf(Gd::class, $oShape);
-        $this->assertEquals('PHPPresentation logo', $oShape->getName());
-        $this->assertEquals('PHPPresentation logo', $oShape->getDescription());
-        $this->assertEquals(36, $oShape->getHeight());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(10, $oShape->getOffsetY());
-        $this->assertEquals('image/gif', $oShape->getMimeType());
-        $this->assertTrue($oShape->getShadow()->isVisible());
-        $this->assertEquals(45, $oShape->getShadow()->getDirection());
-        $this->assertEquals(10, $oShape->getShadow()->getDistance());
+        self::assertInstanceOf(Gd::class, $oShape);
+        self::assertEquals('PHPPresentation logo', $oShape->getName());
+        self::assertEquals('PHPPresentation logo', $oShape->getDescription());
+        self::assertEquals(36, $oShape->getHeight());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(10, $oShape->getOffsetY());
+        self::assertEquals('image/gif', $oShape->getMimeType());
+        self::assertTrue($oShape->getShadow()->isVisible());
+        self::assertEquals(45, $oShape->getShadow()->getDirection());
+        self::assertEquals(10, $oShape->getShadow()->getDistance());
         // Slide 1 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[1];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(200, $oShape->getHeight());
-        $this->assertEquals(600, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(400, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(200, $oShape->getHeight());
+        self::assertEquals(600, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(400, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
-        $this->assertEquals(0, $oParagraph->getSpacingAfter());
-        $this->assertEquals(0, $oParagraph->getSpacingBefore());
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
-        $this->assertEquals(100, $oParagraph->getLineSpacing());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(0, $oParagraph->getSpacingAfter());
+        self::assertEquals(0, $oParagraph->getSpacingBefore());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
+        self::assertEquals(100, $oParagraph->getLineSpacing());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(3, $arrayRichText);
+        self::assertCount(3, $arrayRichText);
         // Slide 1 : Shape 2 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Introduction to', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(28, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Introduction to', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(28, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 1 : Shape 2 : Paragraph 2
         $oRichText = $arrayRichText[1];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $oRichText);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $oRichText);
         // Slide 1 : Shape 2 : Paragraph 3
         $oRichText = $arrayRichText[2];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('PHPPresentation', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(60, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('PHPPresentation', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(60, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
 
         // Slide 2
         $oSlide2 = $oPhpPresentation->getSlide(1);
         $arrayShape = (array) $oSlide2->getShapeCollection();
-        $this->assertCount(3, $arrayShape);
+        self::assertCount(3, $arrayShape);
         // Slide 2 : Shape 1
         /** @var Gd $oShape */
         $oShape = $arrayShape[0];
-        $this->assertInstanceOf(Gd::class, $oShape);
-        $this->assertEquals('PHPPresentation logo', $oShape->getName());
-        $this->assertEquals('PHPPresentation logo', $oShape->getDescription());
-        $this->assertEquals(36, $oShape->getHeight());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(10, $oShape->getOffsetY());
-        $this->assertEquals('image/gif', $oShape->getMimeType());
-        $this->assertTrue($oShape->getShadow()->isVisible());
-        $this->assertEquals(45, $oShape->getShadow()->getDirection());
-        $this->assertEquals(10, $oShape->getShadow()->getDistance());
+        self::assertInstanceOf(Gd::class, $oShape);
+        self::assertEquals('PHPPresentation logo', $oShape->getName());
+        self::assertEquals('PHPPresentation logo', $oShape->getDescription());
+        self::assertEquals(36, $oShape->getHeight());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(10, $oShape->getOffsetY());
+        self::assertEquals('image/gif', $oShape->getMimeType());
+        self::assertTrue($oShape->getShadow()->isVisible());
+        self::assertEquals(45, $oShape->getShadow()->getDirection());
+        self::assertEquals(10, $oShape->getShadow()->getDistance());
         // Slide 2 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[1];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(100, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(50, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(100, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(50, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         // Slide 2 : Shape 2 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('What is PHPPresentation?', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(48, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('What is PHPPresentation?', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(48, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 2 : Shape 3
         /** @var RichText $oShape */
         $oShape = $arrayShape[2];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(600, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(130, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(600, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(130, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(4, $arrayParagraphs);
+        self::assertCount(4, $arrayParagraphs);
         // Slide 2 : Shape 3 : Paragraph 1
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('A class library', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('A class library', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 2 : Shape 3 : Paragraph 2
         $oParagraph = $arrayParagraphs[1];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Written in PHP', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Written in PHP', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 2 : Shape 3 : Paragraph 3
         $oParagraph = $arrayParagraphs[2];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Representing a presentation', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Representing a presentation', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 2 : Shape 3 : Paragraph 4
         $oParagraph = $arrayParagraphs[3];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Supports writing to different file formats', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Supports writing to different file formats', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
 
         // Slide 3
         $oSlide2 = $oPhpPresentation->getSlide(2);
         $arrayShape = (array) $oSlide2->getShapeCollection();
-        $this->assertCount(3, $arrayShape);
+        self::assertCount(3, $arrayShape);
         // Slide 3 : Shape 1
         /** @var Gd $oShape */
         $oShape = $arrayShape[0];
-        $this->assertInstanceOf(Gd::class, $oShape);
-        $this->assertEquals('PHPPresentation logo', $oShape->getName());
-        $this->assertEquals('PHPPresentation logo', $oShape->getDescription());
-        $this->assertEquals(36, $oShape->getHeight());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(10, $oShape->getOffsetY());
-        $this->assertEquals('image/gif', $oShape->getMimeType());
-        $this->assertTrue($oShape->getShadow()->isVisible());
-        $this->assertEquals(45, $oShape->getShadow()->getDirection());
-        $this->assertEquals(10, $oShape->getShadow()->getDistance());
+        self::assertInstanceOf(Gd::class, $oShape);
+        self::assertEquals('PHPPresentation logo', $oShape->getName());
+        self::assertEquals('PHPPresentation logo', $oShape->getDescription());
+        self::assertEquals(36, $oShape->getHeight());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(10, $oShape->getOffsetY());
+        self::assertEquals('image/gif', $oShape->getMimeType());
+        self::assertTrue($oShape->getShadow()->isVisible());
+        self::assertEquals(45, $oShape->getShadow()->getDirection());
+        self::assertEquals(10, $oShape->getShadow()->getDistance());
         // Slide 3 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[1];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(100, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(50, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(100, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(50, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
-        $this->assertEquals(0, $oParagraph->getSpacingAfter());
-        $this->assertEquals(0, $oParagraph->getSpacingBefore());
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
-        $this->assertEquals(100, $oParagraph->getLineSpacing());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(0, $oParagraph->getSpacingAfter());
+        self::assertEquals(0, $oParagraph->getSpacingBefore());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
+        self::assertEquals(100, $oParagraph->getLineSpacing());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         // Slide 3 : Shape 2 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('What\'s the point?', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(48, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('What\'s the point?', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(48, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[2];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(600, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(130, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(600, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(130, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(8, $arrayParagraphs);
+        self::assertCount(8, $arrayParagraphs);
         // Slide 3 : Shape 3 : Paragraph 1
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(0, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(0, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Generate slide decks', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Generate slide decks', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 2
         $oParagraph = $arrayParagraphs[1];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Represent business data', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Represent business data', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 3
         $oParagraph = $arrayParagraphs[2];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Show a family slide show', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Show a family slide show', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 4
         $oParagraph = $arrayParagraphs[3];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('...', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('...', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 5
         $oParagraph = $arrayParagraphs[4];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(0, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(25, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(0, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Export these to different formats', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Export these to different formats', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 6
         $oParagraph = $arrayParagraphs[5];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('PHPPresentation 2007', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('PHPPresentation 2007', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 7
         $oParagraph = $arrayParagraphs[6];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Serialized', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Serialized', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 3 : Shape 3 : Paragraph 8
         $oParagraph = $arrayParagraphs[7];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(-25, $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(1, $oParagraph->getAlignment()->getLevel());
-        $this->assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(75, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(-25, $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(1, $oParagraph->getAlignment()->getLevel());
+        self::assertEquals(Bullet::TYPE_BULLET, $oParagraph->getBulletStyle()->getBulletType());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('... (more to come) ...', $oRichText->getText());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('... (more to come) ...', $oRichText->getText());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
 
         // Slide 4
         $oSlide3 = $oPhpPresentation->getSlide(3);
         $arrayShape = (array) $oSlide3->getShapeCollection();
-        $this->assertCount(3, $arrayShape);
+        self::assertCount(3, $arrayShape);
         // Slide 4 : Shape 1
         /** @var Gd $oShape */
         $oShape = $arrayShape[0];
-        $this->assertInstanceOf(Gd::class, $oShape);
-        $this->assertEquals('PHPPresentation logo', $oShape->getName());
-        $this->assertEquals('PHPPresentation logo', $oShape->getDescription());
-        $this->assertEquals(36, $oShape->getHeight());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(10, $oShape->getOffsetY());
-        $this->assertEquals('image/gif', $oShape->getMimeType());
-        $this->assertTrue($oShape->getShadow()->isVisible());
-        $this->assertEquals(45, $oShape->getShadow()->getDirection());
-        $this->assertEquals(10, $oShape->getShadow()->getDistance());
+        self::assertInstanceOf(Gd::class, $oShape);
+        self::assertEquals('PHPPresentation logo', $oShape->getName());
+        self::assertEquals('PHPPresentation logo', $oShape->getDescription());
+        self::assertEquals(36, $oShape->getHeight());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(10, $oShape->getOffsetY());
+        self::assertEquals('image/gif', $oShape->getMimeType());
+        self::assertTrue($oShape->getShadow()->isVisible());
+        self::assertEquals(45, $oShape->getShadow()->getDirection());
+        self::assertEquals(10, $oShape->getShadow()->getDistance());
         // Slide 4 : Shape 2
         /** @var RichText $oShape */
         $oShape = $arrayShape[1];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(100, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(50, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(100, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(50, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
-        $this->assertEquals(0, $oParagraph->getSpacingAfter());
-        $this->assertEquals(0, $oParagraph->getSpacingBefore());
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
-        $this->assertEquals(100, $oParagraph->getLineSpacing());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(0, $oParagraph->getSpacingAfter());
+        self::assertEquals(0, $oParagraph->getSpacingBefore());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
+        self::assertEquals(100, $oParagraph->getLineSpacing());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(1, $arrayRichText);
+        self::assertCount(1, $arrayRichText);
         // Slide 4 : Shape 2 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Need more info?', $oRichText->getText());
-        $this->assertTrue($oRichText->getFont()->isBold());
-        $this->assertEquals(48, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Need more info?', $oRichText->getText());
+        self::assertTrue($oRichText->getFont()->isBold());
+        self::assertEquals(48, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 4 : Shape 3
         /** @var RichText $oShape */
         $oShape = $arrayShape[2];
-        $this->assertInstanceOf(RichText::class, $oShape);
-        $this->assertEquals(600, $oShape->getHeight());
-        $this->assertEquals(930, $oShape->getWidth());
-        $this->assertEquals(10, $oShape->getOffsetX());
-        $this->assertEquals(130, $oShape->getOffsetY());
+        self::assertInstanceOf(RichText::class, $oShape);
+        self::assertEquals(600, $oShape->getHeight());
+        self::assertEquals(930, $oShape->getWidth());
+        self::assertEquals(10, $oShape->getOffsetX());
+        self::assertEquals(130, $oShape->getOffsetY());
         $arrayParagraphs = $oShape->getParagraphs();
-        $this->assertCount(1, $arrayParagraphs);
+        self::assertCount(1, $arrayParagraphs);
         $oParagraph = $arrayParagraphs[0];
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertFalse($oParagraph->getAlignment()->isRTL());
-        $this->assertEquals(0, $oParagraph->getSpacingAfter());
-        $this->assertEquals(0, $oParagraph->getSpacingBefore());
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
-        $this->assertEquals(100, $oParagraph->getLineSpacing());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $oParagraph->getAlignment()->getHorizontal());
+        self::assertFalse($oParagraph->getAlignment()->isRTL());
+        self::assertEquals(0, $oParagraph->getSpacingAfter());
+        self::assertEquals(0, $oParagraph->getSpacingBefore());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $oParagraph->getLineSpacingMode());
+        self::assertEquals(100, $oParagraph->getLineSpacing());
         $arrayRichText = $oParagraph->getRichTextElements();
-        $this->assertCount(3, $arrayRichText);
+        self::assertCount(3, $arrayRichText);
         // Slide 4 : Shape 3 : Paragraph 1
         $oRichText = $arrayRichText[0];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
-        $this->assertEquals('Check the project site on GitHub:', $oRichText->getText());
-        $this->assertFalse($oRichText->getFont()->isBold());
-        $this->assertEquals(36, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $oRichText);
+        self::assertEquals('Check the project site on GitHub:', $oRichText->getText());
+        self::assertFalse($oRichText->getFont()->isBold());
+        self::assertEquals(36, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
         // Slide 4 : Shape 3 : Paragraph 2
         $oRichText = $arrayRichText[1];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $oRichText);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $oRichText);
         // Slide 4 : Shape 3 : Paragraph 3
         /** @var RichText\Run $oRichText */
         $oRichText = $arrayRichText[2];
-        $this->assertInstanceOf(RichText\Run::class, $oRichText);
-        $this->assertEquals('https://github.com/PHPOffice/PHPPresentation/', $oRichText->getText());
-        $this->assertFalse($oRichText->getFont()->isBold());
-        $this->assertEquals(32, $oRichText->getFont()->getSize());
-        $this->assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
-        $this->assertTrue($oRichText->hasHyperlink());
-        $this->assertEquals('https://github.com/PHPOffice/PHPPresentation/', $oRichText->getHyperlink()->getUrl());
-        $this->assertEquals('PHPPresentation', $oRichText->getHyperlink()->getTooltip());
-        $this->assertFalse($oRichText->getHyperlink()->isTextColorUsed());
-        $this->assertEquals('Calibri', $oRichText->getFont()->getName());
-        $this->assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
+        self::assertInstanceOf(RichText\Run::class, $oRichText);
+        self::assertEquals('https://github.com/PHPOffice/PHPPresentation/', $oRichText->getText());
+        self::assertFalse($oRichText->getFont()->isBold());
+        self::assertEquals(32, $oRichText->getFont()->getSize());
+        self::assertEquals('FF000000', $oRichText->getFont()->getColor()->getARGB());
+        self::assertTrue($oRichText->hasHyperlink());
+        self::assertEquals('https://github.com/PHPOffice/PHPPresentation/', $oRichText->getHyperlink()->getUrl());
+        self::assertEquals('PHPPresentation', $oRichText->getHyperlink()->getTooltip());
+        self::assertFalse($oRichText->getHyperlink()->isTextColorUsed());
+        self::assertEquals('Calibri', $oRichText->getFont()->getName());
+        self::assertEquals(Font::FORMAT_LATIN, $oRichText->getFont()->getFormat());
     }
 
     public function testMarkAsFinal(): void
@@ -578,14 +577,14 @@ public function testMarkAsFinal(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_12.pptx';
         $object = new PowerPoint2007();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertFalse($oPhpPresentation->getPresentationProperties()->isMarkedAsFinal());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertFalse($oPhpPresentation->getPresentationProperties()->isMarkedAsFinal());
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/PPTX_MarkAsFinal.pptx';
         $object = new PowerPoint2007();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertTrue($oPhpPresentation->getPresentationProperties()->isMarkedAsFinal());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertTrue($oPhpPresentation->getPresentationProperties()->isMarkedAsFinal());
     }
 
     public function testZoom(): void
@@ -593,14 +592,14 @@ public function testZoom(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_12.pptx';
         $object = new PowerPoint2007();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertEquals(1, $oPhpPresentation->getPresentationProperties()->getZoom());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertEquals(1, $oPhpPresentation->getPresentationProperties()->getZoom());
 
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/PPTX_Zoom.pptx';
         $object = new PowerPoint2007();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertEquals(2.68, $oPhpPresentation->getPresentationProperties()->getZoom());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertEquals(2.68, $oPhpPresentation->getPresentationProperties()->getZoom());
     }
 
     public function testSlideLayout(): void
@@ -608,12 +607,12 @@ public function testSlideLayout(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Issue_00150.pptx';
         $object = new PowerPoint2007();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
 
         $masterSlides = $oPhpPresentation->getAllMasterSlides();
-        $this->assertCount(3, $masterSlides);
-        $this->assertCount(11, $masterSlides[0]->getAllSlideLayouts());
-        $this->assertCount(11, $masterSlides[1]->getAllSlideLayouts());
-        $this->assertCount(11, $masterSlides[2]->getAllSlideLayouts());
+        self::assertCount(3, $masterSlides);
+        self::assertCount(11, $masterSlides[0]->getAllSlideLayouts());
+        self::assertCount(11, $masterSlides[1]->getAllSlideLayouts());
+        self::assertCount(11, $masterSlides[2]->getAllSlideLayouts());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Reader/PowerPoint97Test.php b/tests/PhpPresentation/Tests/Reader/PowerPoint97Test.php
index 73cfb5ab64..7b54ecf179 100644
--- a/tests/PhpPresentation/Tests/Reader/PowerPoint97Test.php
+++ b/tests/PhpPresentation/Tests/Reader/PowerPoint97Test.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -40,7 +39,7 @@ public function testCanRead(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_00_01.ppt';
         $object = new PowerPoint97();
 
-        $this->assertTrue($object->canRead($file));
+        self::assertTrue($object->canRead($file));
     }
 
     /**
@@ -51,7 +50,7 @@ public function testCantRead(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/serialized.phppt';
         $object = new PowerPoint97();
 
-        $this->assertFalse($object->canRead($file));
+        self::assertFalse($object->canRead($file));
     }
 
     public function testLoadFileNotExists(): void
@@ -90,11 +89,11 @@ public function testLoadFile01(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_00_01.ppt';
         $object = new PowerPoint97();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertEquals(1, $oPhpPresentation->getSlideCount());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertEquals(1, $oPhpPresentation->getSlideCount());
 
         $oSlide = $oPhpPresentation->getSlide(0);
-        $this->assertCount(2, $oSlide->getShapeCollection());
+        self::assertCount(2, $oSlide->getShapeCollection());
     }
 
     public function testLoadFile02(): void
@@ -102,20 +101,20 @@ public function testLoadFile02(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_00_02.ppt';
         $object = new PowerPoint97();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertEquals(4, $oPhpPresentation->getSlideCount());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertEquals(4, $oPhpPresentation->getSlideCount());
 
         $oSlide = $oPhpPresentation->getSlide(0);
-        $this->assertCount(2, $oSlide->getShapeCollection());
+        self::assertCount(2, $oSlide->getShapeCollection());
 
         $oSlide = $oPhpPresentation->getSlide(1);
-        $this->assertCount(3, $oSlide->getShapeCollection());
+        self::assertCount(3, $oSlide->getShapeCollection());
 
         $oSlide = $oPhpPresentation->getSlide(2);
-        $this->assertCount(3, $oSlide->getShapeCollection());
+        self::assertCount(3, $oSlide->getShapeCollection());
 
         $oSlide = $oPhpPresentation->getSlide(3);
-        $this->assertCount(3, $oSlide->getShapeCollection());
+        self::assertCount(3, $oSlide->getShapeCollection());
     }
 
     public function testLoadFile03(): void
@@ -123,11 +122,11 @@ public function testLoadFile03(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_00_03.ppt';
         $object = new PowerPoint97();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertEquals(1, $oPhpPresentation->getSlideCount());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertEquals(1, $oPhpPresentation->getSlideCount());
 
         $oSlide = $oPhpPresentation->getSlide(0);
-        $this->assertCount(1, $oSlide->getShapeCollection());
+        self::assertCount(1, $oSlide->getShapeCollection());
     }
 
     public function testLoadFile04(): void
@@ -135,10 +134,10 @@ public function testLoadFile04(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/Sample_00_04.ppt';
         $object = new PowerPoint97();
         $oPhpPresentation = $object->load($file);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
-        $this->assertEquals(1, $oPhpPresentation->getSlideCount());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $oPhpPresentation);
+        self::assertEquals(1, $oPhpPresentation->getSlideCount());
 
         $oSlide = $oPhpPresentation->getSlide(0);
-        $this->assertCount(4, $oSlide->getShapeCollection());
+        self::assertCount(4, $oSlide->getShapeCollection());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Reader/SerializedTest.php b/tests/PhpPresentation/Tests/Reader/SerializedTest.php
index a4d79d0a74..bc4824c3f8 100644
--- a/tests/PhpPresentation/Tests/Reader/SerializedTest.php
+++ b/tests/PhpPresentation/Tests/Reader/SerializedTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -41,7 +40,7 @@ public function testCanRead(): void
         $file = PHPPRESENTATION_TESTS_BASE_DIR . '/resources/files/serialized.phppt';
         $object = new Serialized();
 
-        $this->assertTrue($object->canRead($file));
+        self::assertTrue($object->canRead($file));
     }
 
     public function testLoadFileNotExists(): void
diff --git a/tests/PhpPresentation/Tests/Shape/AbstractGraphicTest.php b/tests/PhpPresentation/Tests/Shape/AbstractGraphicTest.php
index 54d6cf41ed..997aac77ea 100644
--- a/tests/PhpPresentation/Tests/Shape/AbstractGraphicTest.php
+++ b/tests/PhpPresentation/Tests/Shape/AbstractGraphicTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,31 +35,31 @@ public function testWidthAndHeight(): void
         $max = 20;
         /** @var AbstractGraphic $stub */
         $stub = $this->getMockForAbstractClass('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic');
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setResizeProportional(false));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidth($min));
-        $this->assertEquals($min, $stub->getWidth());
-        $this->assertEquals(0, $stub->getHeight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setHeight($max));
-        $this->assertEquals($min, $stub->getWidth());
-        $this->assertEquals($max, $stub->getHeight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidthAndHeight($min, $max));
-        $this->assertEquals($min, $stub->getWidth());
-        $this->assertEquals($max, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setResizeProportional(false));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidth($min));
+        self::assertEquals($min, $stub->getWidth());
+        self::assertEquals(0, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setHeight($max));
+        self::assertEquals($min, $stub->getWidth());
+        self::assertEquals($max, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidthAndHeight($min, $max));
+        self::assertEquals($min, $stub->getWidth());
+        self::assertEquals($max, $stub->getHeight());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setResizeProportional(true));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidth($max));
-        $this->assertEquals($max, $stub->getWidth());
-        $this->assertEquals($max * ($max / $min), $stub->getHeight());
-        $this->assertEquals($max, $stub->getWidth());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setHeight($min));
-        $this->assertEquals($min * ($max / ($max * ($max / $min))), $stub->getWidth());
-        $this->assertEquals($min, $stub->getHeight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidthAndHeight($min, $max));
-        $this->assertEquals($min, $stub->getWidth());
-        $this->assertEquals($max, $stub->getHeight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidthAndHeight($max, $min));
-        $this->assertEquals($min * ($min / $max), $stub->getWidth());
-        $this->assertEquals($min, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setResizeProportional(true));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidth($max));
+        self::assertEquals($max, $stub->getWidth());
+        self::assertEquals($max * ($max / $min), $stub->getHeight());
+        self::assertEquals($max, $stub->getWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setHeight($min));
+        self::assertEquals($min * ($max / ($max * ($max / $min))), $stub->getWidth());
+        self::assertEquals($min, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidthAndHeight($min, $max));
+        self::assertEquals($min, $stub->getWidth());
+        self::assertEquals($max, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidthAndHeight($max, $min));
+        self::assertEquals($min * ($min / $max), $stub->getWidth());
+        self::assertEquals($min, $stub->getHeight());
     }
 
     public function testWidthAndHeight2(): void
@@ -69,24 +68,24 @@ public function testWidthAndHeight2(): void
         $max = 20;
         /** @var AbstractGraphic $stub */
         $stub = $this->getMockForAbstractClass('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic');
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setResizeProportional(false));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidth($max));
-        $this->assertEquals($max, $stub->getWidth());
-        $this->assertEquals(0, $stub->getHeight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setHeight($min));
-        $this->assertEquals($max, $stub->getWidth());
-        $this->assertEquals($min, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setResizeProportional(false));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidth($max));
+        self::assertEquals($max, $stub->getWidth());
+        self::assertEquals(0, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setHeight($min));
+        self::assertEquals($max, $stub->getWidth());
+        self::assertEquals($min, $stub->getHeight());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setResizeProportional(true));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidth($max));
-        $this->assertEquals($max, $stub->getWidth());
-        $this->assertEquals($max * ($min / $max), $stub->getHeight());
-        $this->assertEquals($max, $stub->getWidth());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setHeight($min));
-        $this->assertEquals($max * ($min / ($max * ($min / $max))), $stub->getWidth());
-        $this->assertEquals($min, $stub->getHeight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidthAndHeight($min, $max));
-        $this->assertEquals($min, $stub->getWidth());
-        $this->assertEquals($min * ($min / ($max * ($min / ($max * ($min / $max))))), $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setResizeProportional(true));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidth($max));
+        self::assertEquals($max, $stub->getWidth());
+        self::assertEquals($max * ($min / $max), $stub->getHeight());
+        self::assertEquals($max, $stub->getWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setHeight($min));
+        self::assertEquals($max * ($min / ($max * ($min / $max))), $stub->getWidth());
+        self::assertEquals($min, $stub->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\AbstractGraphic', $stub->setWidthAndHeight($min, $max));
+        self::assertEquals($min, $stub->getWidth());
+        self::assertEquals($min * ($min / ($max * ($min / ($max * ($min / $max))))), $stub->getHeight());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/AutoShapeTest.php b/tests/PhpPresentation/Tests/Shape/AutoShapeTest.php
index 9e235e2df7..bc7d5636a3 100644
--- a/tests/PhpPresentation/Tests/Shape/AutoShapeTest.php
+++ b/tests/PhpPresentation/Tests/Shape/AutoShapeTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -30,10 +29,10 @@ public function testConstruct(): void
     {
         $object = new AutoShape();
 
-        $this->assertEquals(AutoShape::TYPE_HEART, $object->getType());
-        $this->assertEquals('', $object->getText());
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
-        $this->assertIsString($object->getHashCode());
+        self::assertEquals(AutoShape::TYPE_HEART, $object->getType());
+        self::assertEquals('', $object->getText());
+        self::assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertIsString($object->getHashCode());
     }
 
     public function testOutline(): void
@@ -42,26 +41,26 @@ public function testOutline(): void
         $mock = $this->getMockBuilder(Outline::class)->getMock();
 
         $object = new AutoShape();
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
-        $this->assertInstanceOf(AutoShape::class, $object->setOutline($mock));
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertInstanceOf(AutoShape::class, $object->setOutline($mock));
+        self::assertInstanceOf(Outline::class, $object->getOutline());
     }
 
     public function testText(): void
     {
         $object = new AutoShape();
 
-        $this->assertEquals('', $object->getText());
-        $this->assertInstanceOf(AutoShape::class, $object->setText('Text'));
-        $this->assertEquals('Text', $object->getText());
+        self::assertEquals('', $object->getText());
+        self::assertInstanceOf(AutoShape::class, $object->setText('Text'));
+        self::assertEquals('Text', $object->getText());
     }
 
     public function testType(): void
     {
         $object = new AutoShape();
 
-        $this->assertEquals(AutoShape::TYPE_HEART, $object->getType());
-        $this->assertInstanceOf(AutoShape::class, $object->setType(AutoShape::TYPE_HEXAGON));
-        $this->assertEquals(AutoShape::TYPE_HEXAGON, $object->getType());
+        self::assertEquals(AutoShape::TYPE_HEART, $object->getType());
+        self::assertInstanceOf(AutoShape::class, $object->setType(AutoShape::TYPE_HEXAGON));
+        self::assertEquals(AutoShape::TYPE_HEXAGON, $object->getType());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/AxisTest.php b/tests/PhpPresentation/Tests/Shape/Chart/AxisTest.php
index 0deac26650..7cf9ee3916 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/AxisTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/AxisTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,10 +36,10 @@ public function testConstruct(): void
     {
         $object = new Axis();
 
-        $this->assertEquals('Axis Title', $object->getTitle());
-        $this->assertInstanceOf(Font::class, $object->getFont());
-        $this->assertNull($object->getMinorGridlines());
-        $this->assertNull($object->getMajorGridlines());
+        self::assertEquals('Axis Title', $object->getTitle());
+        self::assertInstanceOf(Font::class, $object->getFont());
+        self::assertNull($object->getMinorGridlines());
+        self::assertNull($object->getMajorGridlines());
     }
 
     public function testBounds(): void
@@ -48,55 +47,55 @@ public function testBounds(): void
         $value = mt_rand(0, 100);
         $object = new Axis();
 
-        $this->assertNull($object->getMinBounds());
-        $this->assertInstanceOf(Axis::class, $object->setMinBounds($value));
-        $this->assertEquals($value, $object->getMinBounds());
-        $this->assertInstanceOf(Axis::class, $object->setMinBounds());
-        $this->assertNull($object->getMinBounds());
-
-        $this->assertNull($object->getMaxBounds());
-        $this->assertInstanceOf(Axis::class, $object->setMaxBounds($value));
-        $this->assertEquals($value, $object->getMaxBounds());
-        $this->assertInstanceOf(Axis::class, $object->setMaxBounds());
-        $this->assertNull($object->getMaxBounds());
+        self::assertNull($object->getMinBounds());
+        self::assertInstanceOf(Axis::class, $object->setMinBounds($value));
+        self::assertEquals($value, $object->getMinBounds());
+        self::assertInstanceOf(Axis::class, $object->setMinBounds());
+        self::assertNull($object->getMinBounds());
+
+        self::assertNull($object->getMaxBounds());
+        self::assertInstanceOf(Axis::class, $object->setMaxBounds($value));
+        self::assertEquals($value, $object->getMaxBounds());
+        self::assertInstanceOf(Axis::class, $object->setMaxBounds());
+        self::assertNull($object->getMaxBounds());
     }
 
     public function testCrossesAt(): void
     {
         $object = new Axis();
 
-        $this->assertEquals(Axis::CROSSES_AUTO, $object->getCrossesAt());
-        $this->assertInstanceOf(Axis::class, $object->setCrossesAt(Axis::CROSSES_MAX));
-        $this->assertEquals(Axis::CROSSES_MAX, $object->getCrossesAt());
+        self::assertEquals(Axis::CROSSES_AUTO, $object->getCrossesAt());
+        self::assertInstanceOf(Axis::class, $object->setCrossesAt(Axis::CROSSES_MAX));
+        self::assertEquals(Axis::CROSSES_MAX, $object->getCrossesAt());
     }
 
     public function testIsReversedOrder(): void
     {
         $object = new Axis();
-        $this->assertFalse($object->isReversedOrder());
-        $this->assertInstanceOf(Axis::class, $object->setIsReversedOrder(true));
-        $this->assertTrue($object->isReversedOrder());
-        $this->assertInstanceOf(Axis::class, $object->setIsReversedOrder(false));
-        $this->assertFalse($object->isReversedOrder());
+        self::assertFalse($object->isReversedOrder());
+        self::assertInstanceOf(Axis::class, $object->setIsReversedOrder(true));
+        self::assertTrue($object->isReversedOrder());
+        self::assertInstanceOf(Axis::class, $object->setIsReversedOrder(false));
+        self::assertFalse($object->isReversedOrder());
     }
 
     public function testFont(): void
     {
         $object = new Axis();
 
-        $this->assertInstanceOf(Axis::class, $object->setFont());
-        $this->assertNull($object->getFont());
-        $this->assertInstanceOf(Axis::class, $object->setFont(new Font()));
-        $this->assertInstanceOf(Font::class, $object->getFont());
+        self::assertInstanceOf(Axis::class, $object->setFont());
+        self::assertNull($object->getFont());
+        self::assertInstanceOf(Axis::class, $object->setFont(new Font()));
+        self::assertInstanceOf(Font::class, $object->getFont());
     }
 
     public function testFormatCode(): void
     {
         $object = new Axis();
-        $this->assertInstanceOf(Axis::class, $object->setFormatCode());
-        $this->assertEquals('', $object->getFormatCode());
-        $this->assertInstanceOf(Axis::class, $object->setFormatCode('AAAA'));
-        $this->assertEquals('AAAA', $object->getFormatCode());
+        self::assertInstanceOf(Axis::class, $object->setFormatCode());
+        self::assertEquals('', $object->getFormatCode());
+        self::assertInstanceOf(Axis::class, $object->setFormatCode('AAAA'));
+        self::assertEquals('AAAA', $object->getFormatCode());
     }
 
     public function testGridLines(): void
@@ -106,10 +105,10 @@ public function testGridLines(): void
         /** @var Gridlines $oMock */
         $oMock = $this->getMockBuilder(Gridlines::class)->getMock();
 
-        $this->assertInstanceOf(Axis::class, $object->setMajorGridlines($oMock));
-        $this->assertInstanceOf(Gridlines::class, $object->getMajorGridlines());
-        $this->assertInstanceOf(Axis::class, $object->setMinorGridlines($oMock));
-        $this->assertInstanceOf(Gridlines::class, $object->getMinorGridlines());
+        self::assertInstanceOf(Axis::class, $object->setMajorGridlines($oMock));
+        self::assertInstanceOf(Gridlines::class, $object->getMajorGridlines());
+        self::assertInstanceOf(Axis::class, $object->setMinorGridlines($oMock));
+        self::assertInstanceOf(Gridlines::class, $object->getMinorGridlines());
     }
 
     public function testHashIndex(): void
@@ -117,32 +116,32 @@ public function testHashIndex(): void
         $object = new Axis();
         $value = mt_rand(1, 100);
 
-        $this->assertEmpty($object->getHashIndex());
-        $this->assertInstanceOf(Axis::class, $object->setHashIndex($value));
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEmpty($object->getHashIndex());
+        self::assertInstanceOf(Axis::class, $object->setHashIndex($value));
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testIsVisible(): void
     {
         $object = new Axis();
-        $this->assertTrue($object->isVisible());
-        $this->assertInstanceOf(Axis::class, $object->setIsVisible(false));
-        $this->assertFalse($object->isVisible());
-        $this->assertInstanceOf(Axis::class, $object->setIsVisible(true));
-        $this->assertTrue($object->isVisible());
+        self::assertTrue($object->isVisible());
+        self::assertInstanceOf(Axis::class, $object->setIsVisible(false));
+        self::assertFalse($object->isVisible());
+        self::assertInstanceOf(Axis::class, $object->setIsVisible(true));
+        self::assertTrue($object->isVisible());
     }
 
     public function testLabelRotation(): void
     {
         $object = new Axis();
-        $this->assertEquals(0, $object->getTitleRotation());
-        $this->assertInstanceOf(Axis::class, $object->setTitleRotation(-1));
-        $this->assertEquals(0, $object->getTitleRotation());
-        $this->assertInstanceOf(Axis::class, $object->setTitleRotation(361));
-        $this->assertEquals(360, $object->getTitleRotation());
-        $value = rand(0, 360);
-        $this->assertInstanceOf(Axis::class, $object->setTitleRotation($value));
-        $this->assertEquals($value, $object->getTitleRotation());
+        self::assertEquals(0, $object->getTitleRotation());
+        self::assertInstanceOf(Axis::class, $object->setTitleRotation(-1));
+        self::assertEquals(0, $object->getTitleRotation());
+        self::assertInstanceOf(Axis::class, $object->setTitleRotation(361));
+        self::assertEquals(360, $object->getTitleRotation());
+        $value = mt_rand(0, 360);
+        self::assertInstanceOf(Axis::class, $object->setTitleRotation($value));
+        self::assertEquals($value, $object->getTitleRotation());
     }
 
     public function testOutline(): void
@@ -151,24 +150,24 @@ public function testOutline(): void
         $oMock = $this->getMockBuilder(Outline::class)->getMock();
 
         $object = new Axis();
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
-        $this->assertInstanceOf(Axis::class, $object->setOutline($oMock));
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertInstanceOf(Axis::class, $object->setOutline($oMock));
+        self::assertInstanceOf(Outline::class, $object->getOutline());
     }
 
     public function testTickLabelPosition(): void
     {
         $object = new Axis();
 
-        $this->assertEquals(Axis::TICK_LABEL_POSITION_NEXT_TO, $object->getTickLabelPosition());
-        $this->assertInstanceOf(Axis::class, $object->setTickLabelPosition(Axis::TICK_LABEL_POSITION_HIGH));
-        $this->assertEquals(Axis::TICK_LABEL_POSITION_HIGH, $object->getTickLabelPosition());
-        $this->assertInstanceOf(Axis::class, $object->setTickLabelPosition(Axis::TICK_LABEL_POSITION_NEXT_TO));
-        $this->assertEquals(Axis::TICK_LABEL_POSITION_NEXT_TO, $object->getTickLabelPosition());
-        $this->assertInstanceOf(Axis::class, $object->setTickLabelPosition(Axis::TICK_LABEL_POSITION_LOW));
-        $this->assertEquals(Axis::TICK_LABEL_POSITION_LOW, $object->getTickLabelPosition());
-        $this->assertInstanceOf(Axis::class, $object->setTickLabelPosition('Unauthorized'));
-        $this->assertEquals(Axis::TICK_LABEL_POSITION_LOW, $object->getTickLabelPosition());
+        self::assertEquals(Axis::TICK_LABEL_POSITION_NEXT_TO, $object->getTickLabelPosition());
+        self::assertInstanceOf(Axis::class, $object->setTickLabelPosition(Axis::TICK_LABEL_POSITION_HIGH));
+        self::assertEquals(Axis::TICK_LABEL_POSITION_HIGH, $object->getTickLabelPosition());
+        self::assertInstanceOf(Axis::class, $object->setTickLabelPosition(Axis::TICK_LABEL_POSITION_NEXT_TO));
+        self::assertEquals(Axis::TICK_LABEL_POSITION_NEXT_TO, $object->getTickLabelPosition());
+        self::assertInstanceOf(Axis::class, $object->setTickLabelPosition(Axis::TICK_LABEL_POSITION_LOW));
+        self::assertEquals(Axis::TICK_LABEL_POSITION_LOW, $object->getTickLabelPosition());
+        self::assertInstanceOf(Axis::class, $object->setTickLabelPosition('Unauthorized'));
+        self::assertEquals(Axis::TICK_LABEL_POSITION_LOW, $object->getTickLabelPosition());
     }
 
     public function testTickMark(): void
@@ -176,25 +175,25 @@ public function testTickMark(): void
         $value = Axis::TICK_MARK_INSIDE;
         $object = new Axis();
 
-        $this->assertEquals(Axis::TICK_MARK_NONE, $object->getMinorTickMark());
-        $this->assertInstanceOf(Axis::class, $object->setMinorTickMark($value));
-        $this->assertEquals($value, $object->getMinorTickMark());
-        $this->assertInstanceOf(Axis::class, $object->setMinorTickMark());
-        $this->assertEquals(Axis::TICK_MARK_NONE, $object->getMinorTickMark());
-
-        $this->assertEquals(Axis::TICK_MARK_NONE, $object->getMajorTickMark());
-        $this->assertInstanceOf(Axis::class, $object->setMajorTickMark($value));
-        $this->assertEquals($value, $object->getMajorTickMark());
-        $this->assertInstanceOf(Axis::class, $object->setMajorTickMark());
-        $this->assertEquals(Axis::TICK_MARK_NONE, $object->getMajorTickMark());
+        self::assertEquals(Axis::TICK_MARK_NONE, $object->getMinorTickMark());
+        self::assertInstanceOf(Axis::class, $object->setMinorTickMark($value));
+        self::assertEquals($value, $object->getMinorTickMark());
+        self::assertInstanceOf(Axis::class, $object->setMinorTickMark());
+        self::assertEquals(Axis::TICK_MARK_NONE, $object->getMinorTickMark());
+
+        self::assertEquals(Axis::TICK_MARK_NONE, $object->getMajorTickMark());
+        self::assertInstanceOf(Axis::class, $object->setMajorTickMark($value));
+        self::assertEquals($value, $object->getMajorTickMark());
+        self::assertInstanceOf(Axis::class, $object->setMajorTickMark());
+        self::assertEquals(Axis::TICK_MARK_NONE, $object->getMajorTickMark());
     }
 
     public function testTitle(): void
     {
         $object = new Axis();
-        $this->assertEquals('Axis Title', $object->getTitle());
-        $this->assertInstanceOf(Axis::class, $object->setTitle('AAAA'));
-        $this->assertEquals('AAAA', $object->getTitle());
+        self::assertEquals('Axis Title', $object->getTitle());
+        self::assertInstanceOf(Axis::class, $object->setTitle('AAAA'));
+        self::assertEquals('AAAA', $object->getTitle());
     }
 
     public function testUnit(): void
@@ -202,16 +201,16 @@ public function testUnit(): void
         $value = mt_rand(0, 100);
         $object = new Axis();
 
-        $this->assertNull($object->getMinorUnit());
-        $this->assertInstanceOf(Axis::class, $object->setMinorUnit($value));
-        $this->assertEquals($value, $object->getMinorUnit());
-        $this->assertInstanceOf(Axis::class, $object->setMinorUnit());
-        $this->assertNull($object->getMinorUnit());
-
-        $this->assertNull($object->getMajorUnit());
-        $this->assertInstanceOf(Axis::class, $object->setMajorUnit($value));
-        $this->assertEquals($value, $object->getMajorUnit());
-        $this->assertInstanceOf(Axis::class, $object->setMajorUnit());
-        $this->assertNull($object->getMajorUnit());
+        self::assertNull($object->getMinorUnit());
+        self::assertInstanceOf(Axis::class, $object->setMinorUnit($value));
+        self::assertEquals($value, $object->getMinorUnit());
+        self::assertInstanceOf(Axis::class, $object->setMinorUnit());
+        self::assertNull($object->getMinorUnit());
+
+        self::assertNull($object->getMajorUnit());
+        self::assertInstanceOf(Axis::class, $object->setMajorUnit($value));
+        self::assertEquals($value, $object->getMajorUnit());
+        self::assertInstanceOf(Axis::class, $object->setMajorUnit());
+        self::assertNull($object->getMajorUnit());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/GridlinesTest.php b/tests/PhpPresentation/Tests/Shape/Chart/GridlinesTest.php
index fe0e964519..3b7e37fd29 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/GridlinesTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/GridlinesTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -30,7 +29,7 @@ public function testConstruct(): void
     {
         $object = new Gridlines();
 
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertInstanceOf(Outline::class, $object->getOutline());
     }
 
     public function testGetSetOutline(): void
@@ -40,8 +39,8 @@ public function testGetSetOutline(): void
         /** @var Outline $oStub */
         $oStub = $this->getMockBuilder(Outline::class)->getMock();
 
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Gridlines', $object->setOutline($oStub));
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Gridlines', $object->setOutline($oStub));
+        self::assertInstanceOf(Outline::class, $object->getOutline());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/LegendTest.php b/tests/PhpPresentation/Tests/Shape/Chart/LegendTest.php
index 3b57adbb25..6ee4ce60de 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/LegendTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/LegendTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -38,46 +37,46 @@ public function testConstruct(): void
     {
         $object = new Legend();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getBorder());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Alignment', $object->getAlignment());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getBorder());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Alignment', $object->getAlignment());
     }
 
     public function testAlignment(): void
     {
         $object = new Legend();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setAlignment(new Alignment()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Alignment', $object->getAlignment());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setAlignment(new Alignment()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Alignment', $object->getAlignment());
     }
 
     public function testBorder(): void
     {
         $object = new Legend();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getBorder());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setBorder(new Border()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getBorder());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getBorder());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setBorder(new Border()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getBorder());
     }
 
     public function testFill(): void
     {
         $object = new Legend();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setFill(new Fill()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setFill(new Fill()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
     }
 
     public function testFont(): void
     {
         $object = new Legend();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setFont());
-        $this->assertNull($object->getFont());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setFont(new Font()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setFont());
+        self::assertNull($object->getFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setFont(new Font()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
     }
 
     public function testHashIndex(): void
@@ -85,9 +84,9 @@ public function testHashIndex(): void
         $object = new Legend();
         $value = mt_rand(1, 100);
 
-        $this->assertEmpty($object->getHashIndex());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setHashIndex($value));
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEmpty($object->getHashIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setHashIndex($value));
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testHeight(): void
@@ -95,10 +94,10 @@ public function testHeight(): void
         $object = new Legend();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setHeight());
-        $this->assertEquals(0, $object->getHeight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setHeight($value));
-        $this->assertEquals($value, $object->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setHeight());
+        self::assertEquals(0, $object->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setHeight($value));
+        self::assertEquals($value, $object->getHeight());
     }
 
     public function testOffsetX(): void
@@ -106,10 +105,10 @@ public function testOffsetX(): void
         $object = new Legend();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setOffsetX());
-        $this->assertEquals(0, $object->getOffsetX());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setOffsetX($value));
-        $this->assertEquals($value, $object->getOffsetX());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setOffsetX());
+        self::assertEquals(0, $object->getOffsetX());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setOffsetX($value));
+        self::assertEquals($value, $object->getOffsetX());
     }
 
     public function testOffsetY(): void
@@ -117,32 +116,32 @@ public function testOffsetY(): void
         $object = new Legend();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setOffsetY());
-        $this->assertEquals(0, $object->getOffsetY());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setOffsetY($value));
-        $this->assertEquals($value, $object->getOffsetY());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setOffsetY());
+        self::assertEquals(0, $object->getOffsetY());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setOffsetY($value));
+        self::assertEquals($value, $object->getOffsetY());
     }
 
     public function testPosition(): void
     {
         $object = new Legend();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setPosition());
-        $this->assertEquals(Legend::POSITION_RIGHT, $object->getPosition());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setPosition(Legend::POSITION_BOTTOM));
-        $this->assertEquals(Legend::POSITION_BOTTOM, $object->getPosition());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setPosition());
+        self::assertEquals(Legend::POSITION_RIGHT, $object->getPosition());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setPosition(Legend::POSITION_BOTTOM));
+        self::assertEquals(Legend::POSITION_BOTTOM, $object->getPosition());
     }
 
     public function testVisible(): void
     {
         $object = new Legend();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setVisible());
-        $this->assertTrue($object->isVisible());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setVisible(true));
-        $this->assertTrue($object->isVisible());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setVisible(false));
-        $this->assertFalse($object->isVisible());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setVisible());
+        self::assertTrue($object->isVisible());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setVisible(true));
+        self::assertTrue($object->isVisible());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setVisible(false));
+        self::assertFalse($object->isVisible());
     }
 
     public function testWidth(): void
@@ -150,9 +149,9 @@ public function testWidth(): void
         $object = new Legend();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setWidth());
-        $this->assertEquals(0, $object->getWidth());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setWidth($value));
-        $this->assertEquals($value, $object->getWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setWidth());
+        self::assertEquals(0, $object->getWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Legend', $object->setWidth($value));
+        self::assertEquals($value, $object->getWidth());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/MarkerTest.php b/tests/PhpPresentation/Tests/Shape/Chart/MarkerTest.php
index 9904ea6607..5ecf537f25 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/MarkerTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/MarkerTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,24 +35,24 @@ public function testConstruct(): void
     {
         $object = new Marker();
 
-        $this->assertEquals(Marker::SYMBOL_NONE, $object->getSymbol());
-        $this->assertEquals(5, $object->getSize());
+        self::assertEquals(Marker::SYMBOL_NONE, $object->getSymbol());
+        self::assertEquals(5, $object->getSize());
     }
 
     public function testBorder(): void
     {
         $object = new Marker();
 
-        $this->assertInstanceOf(Border::class, $object->getBorder());
-        $this->assertInstanceOf(Marker::class, $object->setBorder(new Border()));
+        self::assertInstanceOf(Border::class, $object->getBorder());
+        self::assertInstanceOf(Marker::class, $object->setBorder(new Border()));
     }
 
     public function testFill(): void
     {
         $object = new Marker();
 
-        $this->assertInstanceOf(Fill::class, $object->getFill());
-        $this->assertInstanceOf(Marker::class, $object->setFill(new Fill()));
+        self::assertInstanceOf(Fill::class, $object->getFill());
+        self::assertInstanceOf(Marker::class, $object->setFill(new Fill()));
     }
 
     public function testSize(): void
@@ -61,8 +60,8 @@ public function testSize(): void
         $object = new Marker();
         $value = mt_rand(1, 100);
 
-        $this->assertInstanceOf(Marker::class, $object->setSize($value));
-        $this->assertEquals($value, $object->getSize());
+        self::assertInstanceOf(Marker::class, $object->setSize($value));
+        self::assertEquals($value, $object->getSize());
     }
 
     public function testSymbol(): void
@@ -71,7 +70,7 @@ public function testSymbol(): void
 
         $expected = Marker::$arraySymbol[array_rand(Marker::$arraySymbol)];
 
-        $this->assertInstanceOf(Marker::class, $object->setSymbol($expected));
-        $this->assertEquals($expected, $object->getSymbol());
+        self::assertInstanceOf(Marker::class, $object->setSymbol($expected));
+        self::assertEquals($expected, $object->getSymbol());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/PlotAreaTest.php b/tests/PhpPresentation/Tests/Shape/Chart/PlotAreaTest.php
index 42c6a193b4..eb2fac276f 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/PlotAreaTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/PlotAreaTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -38,8 +37,8 @@ public function testConstruct(): void
     {
         $object = new PlotArea();
 
-        $this->assertInstanceOf(Axis::class, $object->getAxisX());
-        $this->assertInstanceOf(Axis::class, $object->getAxisY());
+        self::assertInstanceOf(Axis::class, $object->getAxisX());
+        self::assertInstanceOf(Axis::class, $object->getAxisY());
     }
 
     public function testHashIndex(): void
@@ -47,9 +46,9 @@ public function testHashIndex(): void
         $object = new PlotArea();
         $value = mt_rand(1, 100);
 
-        $this->assertEmpty($object->getHashIndex());
-        $this->assertInstanceOf(PlotArea::class, $object->setHashIndex($value));
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEmpty($object->getHashIndex());
+        self::assertInstanceOf(PlotArea::class, $object->setHashIndex($value));
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testHeight(): void
@@ -57,10 +56,10 @@ public function testHeight(): void
         $object = new PlotArea();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf(PlotArea::class, $object->setHeight());
-        $this->assertEquals(0, $object->getHeight());
-        $this->assertInstanceOf(PlotArea::class, $object->setHeight($value));
-        $this->assertEquals($value, $object->getHeight());
+        self::assertInstanceOf(PlotArea::class, $object->setHeight());
+        self::assertEquals(0, $object->getHeight());
+        self::assertInstanceOf(PlotArea::class, $object->setHeight($value));
+        self::assertEquals($value, $object->getHeight());
     }
 
     public function testOffsetX(): void
@@ -68,10 +67,10 @@ public function testOffsetX(): void
         $object = new PlotArea();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf(PlotArea::class, $object->setOffsetX());
-        $this->assertEquals(0, $object->getOffsetX());
-        $this->assertInstanceOf(PlotArea::class, $object->setOffsetX($value));
-        $this->assertEquals($value, $object->getOffsetX());
+        self::assertInstanceOf(PlotArea::class, $object->setOffsetX());
+        self::assertEquals(0, $object->getOffsetX());
+        self::assertInstanceOf(PlotArea::class, $object->setOffsetX($value));
+        self::assertEquals($value, $object->getOffsetX());
     }
 
     public function testOffsetY(): void
@@ -79,18 +78,18 @@ public function testOffsetY(): void
         $object = new PlotArea();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf(PlotArea::class, $object->setOffsetY());
-        $this->assertEquals(0, $object->getOffsetY());
-        $this->assertInstanceOf(PlotArea::class, $object->setOffsetY($value));
-        $this->assertEquals($value, $object->getOffsetY());
+        self::assertInstanceOf(PlotArea::class, $object->setOffsetY());
+        self::assertEquals(0, $object->getOffsetY());
+        self::assertInstanceOf(PlotArea::class, $object->setOffsetY($value));
+        self::assertEquals($value, $object->getOffsetY());
     }
 
     public function testType(): void
     {
         $object = new PlotArea();
 
-        $this->assertInstanceOf(PlotArea::class, $object->setType(new Bar3D()));
-        $this->assertInstanceOf(AbstractType::class, $object->getType());
+        self::assertInstanceOf(PlotArea::class, $object->setType(new Bar3D()));
+        self::assertInstanceOf(AbstractType::class, $object->getType());
     }
 
     public function testTypeException(): void
@@ -107,9 +106,9 @@ public function testWidth(): void
         $object = new PlotArea();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf(PlotArea::class, $object->setWidth());
-        $this->assertEquals(0, $object->getWidth());
-        $this->assertInstanceOf(PlotArea::class, $object->setWidth($value));
-        $this->assertEquals($value, $object->getWidth());
+        self::assertInstanceOf(PlotArea::class, $object->setWidth());
+        self::assertEquals(0, $object->getWidth());
+        self::assertInstanceOf(PlotArea::class, $object->setWidth($value));
+        self::assertEquals($value, $object->getWidth());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/SeriesTest.php b/tests/PhpPresentation/Tests/Shape/Chart/SeriesTest.php
index f3cc6b7b16..fb613676ec 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/SeriesTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/SeriesTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -38,64 +37,64 @@ public function testConstruct(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Fill::class, $object->getFill());
-        $this->assertInstanceOf(Font::class, $object->getFont());
-        $this->assertEquals('Calibri', $object->getFont()->getName());
-        $this->assertEquals(9, $object->getFont()->getSize());
-        $this->assertEquals('Series Title', $object->getTitle());
-        $this->assertIsArray($object->getValues());
-        $this->assertEmpty($object->getValues());
-        $this->assertInstanceOf(Marker::class, $object->getMarker());
-        $this->assertNull($object->getOutline());
-        $this->assertFalse($object->hasShowLegendKey());
+        self::assertInstanceOf(Fill::class, $object->getFill());
+        self::assertInstanceOf(Font::class, $object->getFont());
+        self::assertEquals('Calibri', $object->getFont()->getName());
+        self::assertEquals(9, $object->getFont()->getSize());
+        self::assertEquals('Series Title', $object->getTitle());
+        self::assertIsArray($object->getValues());
+        self::assertEmpty($object->getValues());
+        self::assertInstanceOf(Marker::class, $object->getMarker());
+        self::assertNull($object->getOutline());
+        self::assertFalse($object->hasShowLegendKey());
     }
 
     public function testDataLabelNumFormat(): void
     {
         $object = new Series();
 
-        $this->assertEmpty($object->getDlblNumFormat());
-        $this->assertFalse($object->hasDlblNumFormat());
+        self::assertEmpty($object->getDlblNumFormat());
+        self::assertFalse($object->hasDlblNumFormat());
 
-        $this->assertInstanceOf(Series::class, $object->setDlblNumFormat('#%'));
+        self::assertInstanceOf(Series::class, $object->setDlblNumFormat('#%'));
 
-        $this->assertEquals('#%', $object->getDlblNumFormat());
-        $this->assertTrue($object->hasDlblNumFormat());
+        self::assertEquals('#%', $object->getDlblNumFormat());
+        self::assertTrue($object->hasDlblNumFormat());
 
-        $this->assertInstanceOf(Series::class, $object->setDlblNumFormat());
+        self::assertInstanceOf(Series::class, $object->setDlblNumFormat());
 
-        $this->assertEmpty($object->getDlblNumFormat());
-        $this->assertFalse($object->hasDlblNumFormat());
+        self::assertEmpty($object->getDlblNumFormat());
+        self::assertFalse($object->hasDlblNumFormat());
     }
 
     public function testDataPointFills(): void
     {
         $object = new Series();
 
-        $this->assertIsArray($object->getDataPointFills());
-        $this->assertEmpty($object->getDataPointFills());
+        self::assertIsArray($object->getDataPointFills());
+        self::assertEmpty($object->getDataPointFills());
 
-        $this->assertInstanceOf(Fill::class, $object->getDataPointFill(0));
+        self::assertInstanceOf(Fill::class, $object->getDataPointFill(0));
     }
 
     public function testFill(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setFill());
-        $this->assertNull($object->getFill());
-        $this->assertInstanceOf(Series::class, $object->setFill(new Fill()));
-        $this->assertInstanceOf(Fill::class, $object->getFill());
+        self::assertInstanceOf(Series::class, $object->setFill());
+        self::assertNull($object->getFill());
+        self::assertInstanceOf(Series::class, $object->setFill(new Fill()));
+        self::assertInstanceOf(Fill::class, $object->getFill());
     }
 
     public function testFont(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setFont());
-        $this->assertNull($object->getFont());
-        $this->assertInstanceOf(Series::class, $object->setFont(new Font()));
-        $this->assertInstanceOf(Font::class, $object->getFont());
+        self::assertInstanceOf(Series::class, $object->setFont());
+        self::assertNull($object->getFont());
+        self::assertInstanceOf(Series::class, $object->setFont(new Font()));
+        self::assertInstanceOf(Font::class, $object->getFont());
     }
 
     public function testHashIndex(): void
@@ -103,82 +102,82 @@ public function testHashIndex(): void
         $object = new Series();
         $value = mt_rand(1, 100);
 
-        $this->assertEmpty($object->getHashIndex());
-        $this->assertInstanceOf(Series::class, $object->setHashIndex($value));
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEmpty($object->getHashIndex());
+        self::assertInstanceOf(Series::class, $object->setHashIndex($value));
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testHashCode(): void
     {
         $object = new Series();
 
-        $this->assertEquals(md5($object->getFill()->getHashCode() . $object->getFont()->getHashCode() . var_export($object->getValues(), true) . var_export($object, true) . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($object->getFill()->getHashCode() . $object->getFont()->getHashCode() . var_export($object->getValues(), true) . var_export($object, true) . get_class($object)), $object->getHashCode());
     }
 
     public function testLabelPosition(): void
     {
         $object = new Series();
 
-        $this->assertEmpty($object->getHashIndex());
-        $this->assertInstanceOf(Series::class, $object->setLabelPosition(Series::LABEL_INSIDEBASE));
-        $this->assertEquals(Series::LABEL_INSIDEBASE, $object->getLabelPosition());
+        self::assertEmpty($object->getHashIndex());
+        self::assertInstanceOf(Series::class, $object->setLabelPosition(Series::LABEL_INSIDEBASE));
+        self::assertEquals(Series::LABEL_INSIDEBASE, $object->getLabelPosition());
     }
 
     public function testMarker(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setMarker(new Marker()));
-        $this->assertInstanceOf(Marker::class, $object->getMarker());
+        self::assertInstanceOf(Series::class, $object->setMarker(new Marker()));
+        self::assertInstanceOf(Marker::class, $object->getMarker());
     }
 
     public function testOutline(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setOutline(new Outline()));
-        $this->assertInstanceOf(Outline::class, $object->getOutline());
+        self::assertInstanceOf(Series::class, $object->setOutline(new Outline()));
+        self::assertInstanceOf(Outline::class, $object->getOutline());
     }
 
     public function testShowCategoryName(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setShowCategoryName(true));
-        $this->assertTrue($object->hasShowCategoryName());
-        $this->assertInstanceOf(Series::class, $object->setShowCategoryName(false));
-        $this->assertFalse($object->hasShowCategoryName());
+        self::assertInstanceOf(Series::class, $object->setShowCategoryName(true));
+        self::assertTrue($object->hasShowCategoryName());
+        self::assertInstanceOf(Series::class, $object->setShowCategoryName(false));
+        self::assertFalse($object->hasShowCategoryName());
     }
 
     public function testShowLeaderLines(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setShowLeaderLines(true));
-        $this->assertTrue($object->hasShowLeaderLines());
-        $this->assertInstanceOf(Series::class, $object->setShowLeaderLines(false));
-        $this->assertFalse($object->hasShowLeaderLines());
+        self::assertInstanceOf(Series::class, $object->setShowLeaderLines(true));
+        self::assertTrue($object->hasShowLeaderLines());
+        self::assertInstanceOf(Series::class, $object->setShowLeaderLines(false));
+        self::assertFalse($object->hasShowLeaderLines());
     }
 
     public function testShowLegendKey(): void
     {
         $object = new Series();
 
-        $this->assertFalse($object->hasShowLegendKey());
-        $this->assertInstanceOf(Series::class, $object->setShowLegendKey(true));
-        $this->assertTrue($object->hasShowLegendKey());
-        $this->assertInstanceOf(Series::class, $object->setShowLegendKey(false));
-        $this->assertFalse($object->hasShowLegendKey());
+        self::assertFalse($object->hasShowLegendKey());
+        self::assertInstanceOf(Series::class, $object->setShowLegendKey(true));
+        self::assertTrue($object->hasShowLegendKey());
+        self::assertInstanceOf(Series::class, $object->setShowLegendKey(false));
+        self::assertFalse($object->hasShowLegendKey());
     }
 
     public function testShowPercentage(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setShowPercentage(true));
-        $this->assertTrue($object->hasShowPercentage());
-        $this->assertInstanceOf(Series::class, $object->setShowPercentage(false));
-        $this->assertFalse($object->hasShowPercentage());
+        self::assertInstanceOf(Series::class, $object->setShowPercentage(true));
+        self::assertTrue($object->hasShowPercentage());
+        self::assertInstanceOf(Series::class, $object->setShowPercentage(false));
+        self::assertFalse($object->hasShowPercentage());
     }
 
     public function testShowSeparator(): void
@@ -186,42 +185,42 @@ public function testShowSeparator(): void
         $value = ';';
         $object = new Series();
 
-        $this->assertFalse($object->hasShowSeparator());
-        $this->assertInstanceOf(Series::class, $object->setSeparator($value));
-        $this->assertEquals($value, $object->getSeparator());
-        $this->assertTrue($object->hasShowSeparator());
-        $this->assertInstanceOf(Series::class, $object->setSeparator(''));
-        $this->assertFalse($object->hasShowPercentage());
+        self::assertFalse($object->hasShowSeparator());
+        self::assertInstanceOf(Series::class, $object->setSeparator($value));
+        self::assertEquals($value, $object->getSeparator());
+        self::assertTrue($object->hasShowSeparator());
+        self::assertInstanceOf(Series::class, $object->setSeparator(''));
+        self::assertFalse($object->hasShowPercentage());
     }
 
     public function testShowSeriesName(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setShowSeriesName(true));
-        $this->assertTrue($object->hasShowSeriesName());
-        $this->assertInstanceOf(Series::class, $object->setShowSeriesName(false));
-        $this->assertFalse($object->hasShowSeriesName());
+        self::assertInstanceOf(Series::class, $object->setShowSeriesName(true));
+        self::assertTrue($object->hasShowSeriesName());
+        self::assertInstanceOf(Series::class, $object->setShowSeriesName(false));
+        self::assertFalse($object->hasShowSeriesName());
     }
 
     public function testShowValue(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setShowValue(true));
-        $this->assertTrue($object->hasShowValue());
-        $this->assertInstanceOf(Series::class, $object->setShowValue(false));
-        $this->assertFalse($object->hasShowValue());
+        self::assertInstanceOf(Series::class, $object->setShowValue(true));
+        self::assertTrue($object->hasShowValue());
+        self::assertInstanceOf(Series::class, $object->setShowValue(false));
+        self::assertFalse($object->hasShowValue());
     }
 
     public function testTitle(): void
     {
         $object = new Series();
 
-        $this->assertInstanceOf(Series::class, $object->setTitle());
-        $this->assertEquals('Series Title', $object->getTitle());
-        $this->assertInstanceOf(Series::class, $object->setTitle('AAAA'));
-        $this->assertEquals('AAAA', $object->getTitle());
+        self::assertInstanceOf(Series::class, $object->setTitle());
+        self::assertEquals('Series Title', $object->getTitle());
+        self::assertInstanceOf(Series::class, $object->setTitle('AAAA'));
+        self::assertEquals('AAAA', $object->getTitle());
     }
 
     public function testValue(): void
@@ -236,14 +235,14 @@ public function testValue(): void
             '3' => 'd',
         ];
 
-        $this->assertIsArray($object->getValues());
-        $this->assertEmpty($object->getValues());
-        $this->assertInstanceOf(Series::class, $object->setValues());
-        $this->assertEmpty($object->getValues());
-        $this->assertInstanceOf(Series::class, $object->setValues($array));
-        $this->assertCount(count($array), $object->getValues());
-        $this->assertInstanceOf(Series::class, $object->addValue('4', 'e'));
-        $this->assertCount(count($array) + 1, $object->getValues());
+        self::assertIsArray($object->getValues());
+        self::assertEmpty($object->getValues());
+        self::assertInstanceOf(Series::class, $object->setValues());
+        self::assertEmpty($object->getValues());
+        self::assertInstanceOf(Series::class, $object->setValues($array));
+        self::assertCount(count($array), $object->getValues());
+        self::assertInstanceOf(Series::class, $object->addValue('4', 'e'));
+        self::assertCount(count($array) + 1, $object->getValues());
     }
 
     public function testClone(): void
@@ -252,7 +251,7 @@ public function testClone(): void
         $object->setOutline(new Outline());
         $clone = clone $object;
 
-        $this->assertInstanceOf(Series::class, $clone);
-        $this->assertInstanceOf(Outline::class, $clone->getOutline());
+        self::assertInstanceOf(Series::class, $clone);
+        self::assertInstanceOf(Outline::class, $clone->getOutline());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/TitleTest.php b/tests/PhpPresentation/Tests/Shape/Chart/TitleTest.php
index a2e076451b..8867186258 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/TitleTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/TitleTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,28 +35,28 @@ public function testConstruct(): void
     {
         $object = new Title();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Alignment', $object->getAlignment());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
-        $this->assertEquals('Calibri', $object->getFont()->getName());
-        $this->assertEquals(18, $object->getFont()->getSize());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Alignment', $object->getAlignment());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
+        self::assertEquals('Calibri', $object->getFont()->getName());
+        self::assertEquals(18, $object->getFont()->getSize());
     }
 
     public function testAlignment(): void
     {
         $object = new Title();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setAlignment(new Alignment()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Alignment', $object->getAlignment());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setAlignment(new Alignment()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Alignment', $object->getAlignment());
     }
 
     public function testFont(): void
     {
         $object = new Title();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setFont());
-        $this->assertNull($object->getFont());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setFont(new Font()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setFont());
+        self::assertNull($object->getFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setFont(new Font()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
     }
 
     public function testHashIndex(): void
@@ -65,9 +64,9 @@ public function testHashIndex(): void
         $object = new Title();
         $value = mt_rand(1, 100);
 
-        $this->assertEmpty($object->getHashIndex());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setHashIndex($value));
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEmpty($object->getHashIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setHashIndex($value));
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testHeight(): void
@@ -75,10 +74,10 @@ public function testHeight(): void
         $object = new Title();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setHeight());
-        $this->assertEquals(0, $object->getHeight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setHeight($value));
-        $this->assertEquals($value, $object->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setHeight());
+        self::assertEquals(0, $object->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setHeight($value));
+        self::assertEquals($value, $object->getHeight());
     }
 
     public function testOffsetX(): void
@@ -86,10 +85,10 @@ public function testOffsetX(): void
         $object = new Title();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setOffsetX());
-        $this->assertEquals(0.01, $object->getOffsetX());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setOffsetX($value));
-        $this->assertEquals($value, $object->getOffsetX());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setOffsetX());
+        self::assertEquals(0.01, $object->getOffsetX());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setOffsetX($value));
+        self::assertEquals($value, $object->getOffsetX());
     }
 
     public function testOffsetY(): void
@@ -97,32 +96,32 @@ public function testOffsetY(): void
         $object = new Title();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setOffsetY());
-        $this->assertEquals(0.01, $object->getOffsetY());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setOffsetY($value));
-        $this->assertEquals($value, $object->getOffsetY());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setOffsetY());
+        self::assertEquals(0.01, $object->getOffsetY());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setOffsetY($value));
+        self::assertEquals($value, $object->getOffsetY());
     }
 
     public function testText(): void
     {
         $object = new Title();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setText());
-        $this->assertNull($object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setText('AAAA'));
-        $this->assertEquals('AAAA', $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setText());
+        self::assertNull($object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setText('AAAA'));
+        self::assertEquals('AAAA', $object->getText());
     }
 
     public function testVisible(): void
     {
         $object = new Title();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setVisible());
-        $this->assertTrue($object->isVisible());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setVisible(true));
-        $this->assertTrue($object->isVisible());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setVisible(false));
-        $this->assertFalse($object->isVisible());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setVisible());
+        self::assertTrue($object->isVisible());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setVisible(true));
+        self::assertTrue($object->isVisible());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setVisible(false));
+        self::assertFalse($object->isVisible());
     }
 
     public function testWidth(): void
@@ -130,9 +129,9 @@ public function testWidth(): void
         $object = new Title();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setWidth());
-        $this->assertEquals(0, $object->getWidth());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setWidth($value));
-        $this->assertEquals($value, $object->getWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setWidth());
+        self::assertEquals(0, $object->getWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $object->setWidth($value));
+        self::assertEquals($value, $object->getWidth());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/AbstractTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/AbstractTest.php
index d19327eba2..0addee5996 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/AbstractTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/AbstractTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,8 +35,8 @@ public function testAxis(): void
     {
         $object = new Scatter();
 
-        $this->assertTrue($object->hasAxisX());
-        $this->assertTrue($object->hasAxisY());
+        self::assertTrue($object->hasAxisX());
+        self::assertTrue($object->hasAxisY());
     }
 
     public function testHashIndex(): void
@@ -45,25 +44,25 @@ public function testHashIndex(): void
         $object = new Scatter();
         $value = mt_rand(1, 100);
 
-        $this->assertEmpty($object->getHashIndex());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Scatter', $object->setHashIndex($value));
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEmpty($object->getHashIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Scatter', $object->setHashIndex($value));
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testSeries(): void
     {
         /** @var AbstractType $stub */
         $stub = $this->getMockForAbstractClass(AbstractType::class);
-        $this->assertEmpty($stub->getSeries());
-        $this->assertIsArray($stub->getSeries());
+        self::assertEmpty($stub->getSeries());
+        self::assertIsArray($stub->getSeries());
 
         $arraySeries = [
             new Series(),
             new Series(),
         ];
-        $this->assertInstanceOf(AbstractType::class, $stub->setSeries($arraySeries));
-        $this->assertIsArray($stub->getSeries());
-        $this->assertCount(count($arraySeries), $stub->getSeries());
+        self::assertInstanceOf(AbstractType::class, $stub->setSeries($arraySeries));
+        self::assertIsArray($stub->getSeries());
+        self::assertCount(count($arraySeries), $stub->getSeries());
     }
 
     public function testClone(): void
@@ -80,8 +79,8 @@ public function testClone(): void
         $stub->setSeries($arraySeries);
         $clone = clone $stub;
 
-        $this->assertInstanceOf(AbstractType::class, $clone);
-        $this->assertIsArray($stub->getSeries());
-        $this->assertCount(count($arraySeries), $stub->getSeries());
+        self::assertInstanceOf(AbstractType::class, $clone);
+        self::assertIsArray($stub->getSeries());
+        self::assertCount(count($arraySeries), $stub->getSeries());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/AreaTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/AreaTest.php
index e1eba28f60..af93fa19c7 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/AreaTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/AreaTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,26 +34,26 @@ public function testData(): void
     {
         $object = new Area();
 
-        $this->assertIsArray($object->getSeries());
-        $this->assertEmpty($object->getSeries());
+        self::assertIsArray($object->getSeries());
+        self::assertEmpty($object->getSeries());
 
         $array = [
             new Series(),
             new Series(),
         ];
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Area', $object->setSeries());
-        $this->assertEmpty($object->getSeries());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Area', $object->setSeries($array));
-        $this->assertCount(count($array), $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Area', $object->setSeries());
+        self::assertEmpty($object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Area', $object->setSeries($array));
+        self::assertCount(count($array), $object->getSeries());
     }
 
     public function testSeries(): void
     {
         $object = new Area();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Area', $object->addSeries(new Series()));
-        $this->assertCount(1, $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Area', $object->addSeries(new Series()));
+        self::assertCount(1, $object->getSeries());
     }
 
     public function testHashCode(): void
@@ -64,6 +63,6 @@ public function testHashCode(): void
         $object = new Area();
         $object->addSeries($oSeries);
 
-        $this->assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/Bar3DTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/Bar3DTest.php
index 68df16e1f9..137d577293 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/Bar3DTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/Bar3DTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,61 +34,61 @@ public function testData(): void
     {
         $object = new Bar3D();
 
-        $this->assertIsArray($object->getSeries());
-        $this->assertEmpty($object->getSeries());
+        self::assertIsArray($object->getSeries());
+        self::assertEmpty($object->getSeries());
 
         $array = [
             new Series(),
             new Series(),
         ];
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setSeries());
-        $this->assertEmpty($object->getSeries());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setSeries($array));
-        $this->assertCount(count($array), $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setSeries());
+        self::assertEmpty($object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setSeries($array));
+        self::assertCount(count($array), $object->getSeries());
     }
 
     public function testSeries(): void
     {
         $object = new Bar3D();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->addSeries(new Series()));
-        $this->assertCount(1, $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->addSeries(new Series()));
+        self::assertCount(1, $object->getSeries());
     }
 
     public function testBarDirection(): void
     {
         $object = new Bar3D();
-        $this->assertEquals(Bar3D::DIRECTION_VERTICAL, $object->getBarDirection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarDirection(Bar3D::DIRECTION_HORIZONTAL));
-        $this->assertEquals(Bar3D::DIRECTION_HORIZONTAL, $object->getBarDirection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarDirection(Bar3D::DIRECTION_VERTICAL));
-        $this->assertEquals(Bar3D::DIRECTION_VERTICAL, $object->getBarDirection());
+        self::assertEquals(Bar3D::DIRECTION_VERTICAL, $object->getBarDirection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarDirection(Bar3D::DIRECTION_HORIZONTAL));
+        self::assertEquals(Bar3D::DIRECTION_HORIZONTAL, $object->getBarDirection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarDirection(Bar3D::DIRECTION_VERTICAL));
+        self::assertEquals(Bar3D::DIRECTION_VERTICAL, $object->getBarDirection());
     }
 
     public function testBarGrouping(): void
     {
         $object = new Bar3D();
-        $this->assertEquals(Bar3D::GROUPING_CLUSTERED, $object->getBarGrouping());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarGrouping(Bar3D::GROUPING_CLUSTERED));
-        $this->assertEquals(Bar3D::GROUPING_CLUSTERED, $object->getBarGrouping());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarGrouping(Bar3D::GROUPING_STACKED));
-        $this->assertEquals(Bar3D::GROUPING_STACKED, $object->getBarGrouping());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarGrouping(Bar3D::GROUPING_PERCENTSTACKED));
-        $this->assertEquals(Bar3D::GROUPING_PERCENTSTACKED, $object->getBarGrouping());
+        self::assertEquals(Bar3D::GROUPING_CLUSTERED, $object->getBarGrouping());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarGrouping(Bar3D::GROUPING_CLUSTERED));
+        self::assertEquals(Bar3D::GROUPING_CLUSTERED, $object->getBarGrouping());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarGrouping(Bar3D::GROUPING_STACKED));
+        self::assertEquals(Bar3D::GROUPING_STACKED, $object->getBarGrouping());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setBarGrouping(Bar3D::GROUPING_PERCENTSTACKED));
+        self::assertEquals(Bar3D::GROUPING_PERCENTSTACKED, $object->getBarGrouping());
     }
 
     public function testGapWidthPercent(): void
     {
         $value = mt_rand(0, 500);
         $object = new Bar3D();
-        $this->assertEquals(150, $object->getGapWidthPercent());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setGapWidthPercent($value));
-        $this->assertEquals($value, $object->getGapWidthPercent());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setGapWidthPercent(-1));
-        $this->assertEquals(0, $object->getGapWidthPercent());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setGapWidthPercent(501));
-        $this->assertEquals(500, $object->getGapWidthPercent());
+        self::assertEquals(150, $object->getGapWidthPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setGapWidthPercent($value));
+        self::assertEquals($value, $object->getGapWidthPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setGapWidthPercent(-1));
+        self::assertEquals(0, $object->getGapWidthPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar3D', $object->setGapWidthPercent(501));
+        self::assertEquals(500, $object->getGapWidthPercent());
     }
 
     public function testHashCode(): void
@@ -99,6 +98,6 @@ public function testHashCode(): void
         $object = new Bar3D();
         $object->addSeries($oSeries);
 
-        $this->assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/BarTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/BarTest.php
index 8b7dbd7dc9..88dd6dab8f 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/BarTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/BarTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,87 +34,87 @@ public function testData(): void
     {
         $object = new Bar();
 
-        $this->assertIsArray($object->getSeries());
-        $this->assertEmpty($object->getSeries());
+        self::assertIsArray($object->getSeries());
+        self::assertEmpty($object->getSeries());
 
         $array = [
             new Series(),
             new Series(),
         ];
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setSeries());
-        $this->assertEmpty($object->getSeries());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setSeries($array));
-        $this->assertCount(count($array), $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setSeries());
+        self::assertEmpty($object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setSeries($array));
+        self::assertCount(count($array), $object->getSeries());
     }
 
     public function testSeries(): void
     {
         $object = new Bar();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->addSeries(new Series()));
-        $this->assertCount(1, $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->addSeries(new Series()));
+        self::assertCount(1, $object->getSeries());
     }
 
     public function testBarDirection(): void
     {
         $object = new Bar();
-        $this->assertEquals(Bar::DIRECTION_VERTICAL, $object->getBarDirection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarDirection(Bar::DIRECTION_HORIZONTAL));
-        $this->assertEquals(Bar::DIRECTION_HORIZONTAL, $object->getBarDirection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarDirection(Bar::DIRECTION_VERTICAL));
-        $this->assertEquals(Bar::DIRECTION_VERTICAL, $object->getBarDirection());
+        self::assertEquals(Bar::DIRECTION_VERTICAL, $object->getBarDirection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarDirection(Bar::DIRECTION_HORIZONTAL));
+        self::assertEquals(Bar::DIRECTION_HORIZONTAL, $object->getBarDirection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarDirection(Bar::DIRECTION_VERTICAL));
+        self::assertEquals(Bar::DIRECTION_VERTICAL, $object->getBarDirection());
     }
 
     public function testBarGrouping(): void
     {
         $object = new Bar();
-        $this->assertEquals(Bar::GROUPING_CLUSTERED, $object->getBarGrouping());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarGrouping(Bar::GROUPING_CLUSTERED));
-        $this->assertEquals(Bar::GROUPING_CLUSTERED, $object->getBarGrouping());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarGrouping(Bar::GROUPING_STACKED));
-        $this->assertEquals(Bar::GROUPING_STACKED, $object->getBarGrouping());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarGrouping(Bar::GROUPING_PERCENTSTACKED));
-        $this->assertEquals(Bar::GROUPING_PERCENTSTACKED, $object->getBarGrouping());
+        self::assertEquals(Bar::GROUPING_CLUSTERED, $object->getBarGrouping());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarGrouping(Bar::GROUPING_CLUSTERED));
+        self::assertEquals(Bar::GROUPING_CLUSTERED, $object->getBarGrouping());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarGrouping(Bar::GROUPING_STACKED));
+        self::assertEquals(Bar::GROUPING_STACKED, $object->getBarGrouping());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setBarGrouping(Bar::GROUPING_PERCENTSTACKED));
+        self::assertEquals(Bar::GROUPING_PERCENTSTACKED, $object->getBarGrouping());
     }
 
     public function testGapWidthPercent(): void
     {
         $value = mt_rand(0, 500);
         $object = new Bar();
-        $this->assertEquals(150, $object->getGapWidthPercent());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setGapWidthPercent($value));
-        $this->assertEquals($value, $object->getGapWidthPercent());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setGapWidthPercent(-1));
-        $this->assertEquals(0, $object->getGapWidthPercent());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setGapWidthPercent(501));
-        $this->assertEquals(500, $object->getGapWidthPercent());
+        self::assertEquals(150, $object->getGapWidthPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setGapWidthPercent($value));
+        self::assertEquals($value, $object->getGapWidthPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setGapWidthPercent(-1));
+        self::assertEquals(0, $object->getGapWidthPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Bar', $object->setGapWidthPercent(501));
+        self::assertEquals(500, $object->getGapWidthPercent());
     }
 
     public function testOverlapWidthPercentDefaults(): void
     {
         $object = new Bar();
-        $this->assertEquals(0, $object->getOverlapWidthPercent());
+        self::assertEquals(0, $object->getOverlapWidthPercent());
 
         $object->setBarGrouping(Bar::GROUPING_STACKED);
-        $this->assertEquals(100, $object->getOverlapWidthPercent());
+        self::assertEquals(100, $object->getOverlapWidthPercent());
         $object->setBarGrouping(Bar::GROUPING_CLUSTERED);
-        $this->assertEquals(0, $object->getOverlapWidthPercent());
+        self::assertEquals(0, $object->getOverlapWidthPercent());
         $object->setBarGrouping(Bar::GROUPING_PERCENTSTACKED);
-        $this->assertEquals(100, $object->getOverlapWidthPercent());
+        self::assertEquals(100, $object->getOverlapWidthPercent());
     }
 
     public function testOverlapWidthPercent(): void
     {
         $value = mt_rand(-100, 100);
         $object = new Bar();
-        $this->assertEquals(0, $object->getOverlapWidthPercent());
-        $this->assertInstanceOf(Bar::class, $object->setOverlapWidthPercent($value));
-        $this->assertEquals($value, $object->getOverlapWidthPercent());
-        $this->assertInstanceOf(Bar::class, $object->setOverlapWidthPercent(101));
-        $this->assertEquals(100, $object->getOverlapWidthPercent());
-        $this->assertInstanceOf(Bar::class, $object->setOverlapWidthPercent(-101));
-        $this->assertEquals(-100, $object->getOverlapWidthPercent());
+        self::assertEquals(0, $object->getOverlapWidthPercent());
+        self::assertInstanceOf(Bar::class, $object->setOverlapWidthPercent($value));
+        self::assertEquals($value, $object->getOverlapWidthPercent());
+        self::assertInstanceOf(Bar::class, $object->setOverlapWidthPercent(101));
+        self::assertEquals(100, $object->getOverlapWidthPercent());
+        self::assertInstanceOf(Bar::class, $object->setOverlapWidthPercent(-101));
+        self::assertEquals(-100, $object->getOverlapWidthPercent());
     }
 
     public function testHashCode(): void
@@ -125,6 +124,6 @@ public function testHashCode(): void
         $object = new Bar();
         $object->addSeries($oSeries);
 
-        $this->assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/DoughnutTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/DoughnutTest.php
index a6c8a22045..8b13b5043b 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/DoughnutTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/DoughnutTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,18 +34,18 @@ public function testData(): void
     {
         $object = new Doughnut();
 
-        $this->assertIsArray($object->getSeries());
-        $this->assertEmpty($object->getSeries());
+        self::assertIsArray($object->getSeries());
+        self::assertEmpty($object->getSeries());
 
         $array = [
             new Series(),
             new Series(),
         ];
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setSeries());
-        $this->assertEmpty($object->getSeries());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setSeries($array));
-        $this->assertCount(count($array), $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setSeries());
+        self::assertEmpty($object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setSeries($array));
+        self::assertCount(count($array), $object->getSeries());
     }
 
     public function testHoleSize(): void
@@ -54,23 +53,23 @@ public function testHoleSize(): void
         $rand = mt_rand(10, 90);
         $object = new Doughnut();
 
-        $this->assertEquals(50, $object->getHoleSize());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setHoleSize(9));
-        $this->assertEquals(10, $object->getHoleSize());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setHoleSize(91));
-        $this->assertEquals(90, $object->getHoleSize());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setHoleSize($rand));
-        $this->assertEquals($rand, $object->getHoleSize());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setHoleSize());
-        $this->assertEquals(50, $object->getHoleSize());
+        self::assertEquals(50, $object->getHoleSize());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setHoleSize(9));
+        self::assertEquals(10, $object->getHoleSize());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setHoleSize(91));
+        self::assertEquals(90, $object->getHoleSize());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setHoleSize($rand));
+        self::assertEquals($rand, $object->getHoleSize());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->setHoleSize());
+        self::assertEquals(50, $object->getHoleSize());
     }
 
     public function testSeries(): void
     {
         $object = new Doughnut();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->addSeries(new Series()));
-        $this->assertCount(1, $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Doughnut', $object->addSeries(new Series()));
+        self::assertCount(1, $object->getSeries());
     }
 
     public function testHashCode(): void
@@ -80,6 +79,6 @@ public function testHashCode(): void
         $object = new Doughnut();
         $object->addSeries($oSeries);
 
-        $this->assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/LineTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/LineTest.php
index 05b6cb6f3f..2a077b2ed9 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/LineTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/LineTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,35 +34,35 @@ public function testData(): void
     {
         $object = new Line();
 
-        $this->assertIsArray($object->getSeries());
-        $this->assertEmpty($object->getSeries());
+        self::assertIsArray($object->getSeries());
+        self::assertEmpty($object->getSeries());
 
         $array = [
             new Series(),
             new Series(),
         ];
 
-        $this->assertInstanceOf(Line::class, $object->setSeries());
-        $this->assertEmpty($object->getSeries());
-        $this->assertInstanceOf(Line::class, $object->setSeries($array));
-        $this->assertCount(count($array), $object->getSeries());
+        self::assertInstanceOf(Line::class, $object->setSeries());
+        self::assertEmpty($object->getSeries());
+        self::assertInstanceOf(Line::class, $object->setSeries($array));
+        self::assertCount(count($array), $object->getSeries());
     }
 
     public function testSeries(): void
     {
         $object = new Line();
 
-        $this->assertInstanceOf(Line::class, $object->addSeries(new Series()));
-        $this->assertCount(1, $object->getSeries());
+        self::assertInstanceOf(Line::class, $object->addSeries(new Series()));
+        self::assertCount(1, $object->getSeries());
     }
 
     public function testSmooth(): void
     {
         $object = new Line();
 
-        $this->assertFalse($object->isSmooth());
-        $this->assertInstanceOf(Line::class, $object->setIsSmooth(true));
-        $this->assertTrue($object->isSmooth());
+        self::assertFalse($object->isSmooth());
+        self::assertInstanceOf(Line::class, $object->setIsSmooth(true));
+        self::assertTrue($object->isSmooth());
     }
 
     public function testHashCode(): void
@@ -73,7 +72,7 @@ public function testHashCode(): void
         $object = new Line();
         $object->addSeries($series);
 
-        $this->assertEquals(
+        self::assertEquals(
             md5(md5($object->isSmooth() ? '1' : '0') . $series->getHashCode() . get_class($object)),
             $object->getHashCode()
         );
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/Pie3DTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/Pie3DTest.php
index 33f825c179..dd259108bf 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/Pie3DTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/Pie3DTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,26 +34,26 @@ public function testData(): void
     {
         $object = new Pie3D();
 
-        $this->assertIsArray($object->getSeries());
-        $this->assertEmpty($object->getSeries());
+        self::assertIsArray($object->getSeries());
+        self::assertEmpty($object->getSeries());
 
         $array = [
             new Series(),
             new Series(),
         ];
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie3D', $object->setSeries());
-        $this->assertEmpty($object->getSeries());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie3D', $object->setSeries($array));
-        $this->assertCount(count($array), $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie3D', $object->setSeries());
+        self::assertEmpty($object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie3D', $object->setSeries($array));
+        self::assertCount(count($array), $object->getSeries());
     }
 
     public function testSeries(): void
     {
         $object = new Pie3D();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie3D', $object->addSeries(new Series()));
-        $this->assertCount(1, $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie3D', $object->addSeries(new Series()));
+        self::assertCount(1, $object->getSeries());
     }
 
     public function testExplosion(): void
@@ -62,9 +61,9 @@ public function testExplosion(): void
         $value = mt_rand(0, 100);
         $object = new Pie3D();
 
-        $this->assertEquals(0, $object->getExplosion());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie3D', $object->setExplosion($value));
-        $this->assertEquals($value, $object->getExplosion());
+        self::assertEquals(0, $object->getExplosion());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie3D', $object->setExplosion($value));
+        self::assertEquals($value, $object->getExplosion());
     }
 
     public function testHashCode(): void
@@ -74,6 +73,6 @@ public function testHashCode(): void
         $object = new Pie3D();
         $object->addSeries($oSeries);
 
-        $this->assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/PieTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/PieTest.php
index 42f5b5d6aa..0ba4387a2a 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/PieTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/PieTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,26 +34,26 @@ public function testData(): void
     {
         $object = new Pie();
 
-        $this->assertIsArray($object->getSeries());
-        $this->assertEmpty($object->getSeries());
+        self::assertIsArray($object->getSeries());
+        self::assertEmpty($object->getSeries());
 
         $array = [
             new Series(),
             new Series(),
         ];
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie', $object->setSeries());
-        $this->assertEmpty($object->getSeries());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie', $object->setSeries($array));
-        $this->assertCount(count($array), $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie', $object->setSeries());
+        self::assertEmpty($object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie', $object->setSeries($array));
+        self::assertCount(count($array), $object->getSeries());
     }
 
     public function testSeries(): void
     {
         $object = new Pie();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie', $object->addSeries(new Series()));
-        $this->assertCount(1, $object->getSeries());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Type\\Pie', $object->addSeries(new Series()));
+        self::assertCount(1, $object->getSeries());
     }
 
     public function testHashCode(): void
@@ -64,6 +63,6 @@ public function testHashCode(): void
         $object = new Pie();
         $object->addSeries($oSeries);
 
-        $this->assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($oSeries->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/RadarTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/RadarTest.php
index 07a3cb2f97..e64621861c 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/RadarTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/RadarTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -33,6 +32,6 @@ public function testHashCode(): void
         $object = new Radar();
         $object->addSeries($series);
 
-        $this->assertEquals(md5($series->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($series->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/Type/ScatterTest.php b/tests/PhpPresentation/Tests/Shape/Chart/Type/ScatterTest.php
index ca8134be77..36727ddbfa 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/Type/ScatterTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/Type/ScatterTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,35 +34,35 @@ public function testData(): void
     {
         $object = new Scatter();
 
-        $this->assertIsArray($object->getSeries());
-        $this->assertEmpty($object->getSeries());
+        self::assertIsArray($object->getSeries());
+        self::assertEmpty($object->getSeries());
 
         $array = [
             new Series(),
             new Series(),
         ];
 
-        $this->assertInstanceOf(Scatter::class, $object->setSeries());
-        $this->assertEmpty($object->getSeries());
-        $this->assertInstanceOf(Scatter::class, $object->setSeries($array));
-        $this->assertCount(count($array), $object->getSeries());
+        self::assertInstanceOf(Scatter::class, $object->setSeries());
+        self::assertEmpty($object->getSeries());
+        self::assertInstanceOf(Scatter::class, $object->setSeries($array));
+        self::assertCount(count($array), $object->getSeries());
     }
 
     public function testSeries(): void
     {
         $object = new Scatter();
 
-        $this->assertInstanceOf(Scatter::class, $object->addSeries(new Series()));
-        $this->assertCount(1, $object->getSeries());
+        self::assertInstanceOf(Scatter::class, $object->addSeries(new Series()));
+        self::assertCount(1, $object->getSeries());
     }
 
     public function testSmooth(): void
     {
         $object = new Scatter();
 
-        $this->assertFalse($object->isSmooth());
-        $this->assertInstanceOf(Scatter::class, $object->setIsSmooth(true));
-        $this->assertTrue($object->isSmooth());
+        self::assertFalse($object->isSmooth());
+        self::assertInstanceOf(Scatter::class, $object->setIsSmooth(true));
+        self::assertTrue($object->isSmooth());
     }
 
     public function testHashCode(): void
@@ -73,7 +72,7 @@ public function testHashCode(): void
         $object = new Scatter();
         $object->addSeries($series);
 
-        $this->assertEquals(
+        self::assertEquals(
             md5(md5($object->isSmooth() ? '1' : '0') . $series->getHashCode() . get_class($object)),
             $object->getHashCode()
         );
diff --git a/tests/PhpPresentation/Tests/Shape/Chart/View3DTest.php b/tests/PhpPresentation/Tests/Shape/Chart/View3DTest.php
index f86d39fb15..cbe311aa9c 100644
--- a/tests/PhpPresentation/Tests/Shape/Chart/View3DTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Chart/View3DTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,10 +34,10 @@ public function testDepthPercent(): void
         $object = new View3D();
         $value = mt_rand(20, 20000);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setDepthPercent());
-        $this->assertEquals(100, $object->getDepthPercent());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setDepthPercent($value));
-        $this->assertEquals($value, $object->getDepthPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setDepthPercent());
+        self::assertEquals(100, $object->getDepthPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setDepthPercent($value));
+        self::assertEquals($value, $object->getDepthPercent());
     }
 
     public function testHashIndex(): void
@@ -46,9 +45,9 @@ public function testHashIndex(): void
         $object = new View3D();
         $value = mt_rand(1, 100);
 
-        $this->assertEmpty($object->getHashIndex());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setHashIndex($value));
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEmpty($object->getHashIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setHashIndex($value));
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testHeightPercent(): void
@@ -56,10 +55,10 @@ public function testHeightPercent(): void
         $object = new View3D();
         $value = mt_rand(5, 500);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setHeightPercent());
-        $this->assertEquals(100, $object->getHeightPercent());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setHeightPercent($value));
-        $this->assertEquals($value, $object->getHeightPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setHeightPercent());
+        self::assertEquals(100, $object->getHeightPercent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setHeightPercent($value));
+        self::assertEquals($value, $object->getHeightPercent());
     }
 
     public function testPerspective(): void
@@ -67,22 +66,22 @@ public function testPerspective(): void
         $object = new View3D();
         $value = mt_rand(0, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setPerspective());
-        $this->assertEquals(30, $object->getPerspective());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setPerspective($value));
-        $this->assertEquals($value, $object->getPerspective());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setPerspective());
+        self::assertEquals(30, $object->getPerspective());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setPerspective($value));
+        self::assertEquals($value, $object->getPerspective());
     }
 
     public function testRightAngleAxes(): void
     {
         $object = new View3D();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRightAngleAxes());
-        $this->assertTrue($object->hasRightAngleAxes());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRightAngleAxes(true));
-        $this->assertTrue($object->hasRightAngleAxes());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRightAngleAxes(false));
-        $this->assertFalse($object->hasRightAngleAxes());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRightAngleAxes());
+        self::assertTrue($object->hasRightAngleAxes());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRightAngleAxes(true));
+        self::assertTrue($object->hasRightAngleAxes());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRightAngleAxes(false));
+        self::assertFalse($object->hasRightAngleAxes());
     }
 
     public function testRotationX(): void
@@ -90,10 +89,10 @@ public function testRotationX(): void
         $object = new View3D();
         $value = mt_rand(-90, 90);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRotationX());
-        $this->assertEquals(0, $object->getRotationX());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRotationX($value));
-        $this->assertEquals($value, $object->getRotationX());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRotationX());
+        self::assertEquals(0, $object->getRotationX());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRotationX($value));
+        self::assertEquals($value, $object->getRotationX());
     }
 
     public function testRotationY(): void
@@ -101,9 +100,9 @@ public function testRotationY(): void
         $object = new View3D();
         $value = mt_rand(-90, 90);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRotationY());
-        $this->assertEquals(0, $object->getRotationY());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRotationY($value));
-        $this->assertEquals($value, $object->getRotationY());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRotationY());
+        self::assertEquals(0, $object->getRotationY());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\View3D', $object->setRotationY($value));
+        self::assertEquals($value, $object->getRotationY());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/ChartTest.php b/tests/PhpPresentation/Tests/Shape/ChartTest.php
index b51d857757..2322df83f9 100644
--- a/tests/PhpPresentation/Tests/Shape/ChartTest.php
+++ b/tests/PhpPresentation/Tests/Shape/ChartTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -34,10 +33,10 @@ public function testConstruct(): void
     {
         $object = new Chart();
 
-        $this->assertInstanceOf(Chart\Title::class, $object->getTitle());
-        $this->assertInstanceOf(Chart\Legend::class, $object->getLegend());
-        $this->assertInstanceOf(Chart\PlotArea::class, $object->getPlotArea());
-        $this->assertInstanceOf(Chart\View3D::class, $object->getView3D());
+        self::assertInstanceOf(Chart\Title::class, $object->getTitle());
+        self::assertInstanceOf(Chart\Legend::class, $object->getLegend());
+        self::assertInstanceOf(Chart\PlotArea::class, $object->getPlotArea());
+        self::assertInstanceOf(Chart\View3D::class, $object->getView3D());
     }
 
     public function testClone(): void
@@ -46,38 +45,38 @@ public function testClone(): void
 
         $oClone = clone $object;
 
-        $this->assertInstanceOf(Chart::class, $oClone);
-        $this->assertInstanceOf(Chart\Title::class, $oClone->getTitle());
-        $this->assertInstanceOf(Chart\Legend::class, $oClone->getLegend());
-        $this->assertInstanceOf(Chart\PlotArea::class, $oClone->getPlotArea());
-        $this->assertInstanceOf(Chart\View3D::class, $oClone->getView3D());
+        self::assertInstanceOf(Chart::class, $oClone);
+        self::assertInstanceOf(Chart\Title::class, $oClone->getTitle());
+        self::assertInstanceOf(Chart\Legend::class, $oClone->getLegend());
+        self::assertInstanceOf(Chart\PlotArea::class, $oClone->getPlotArea());
+        self::assertInstanceOf(Chart\View3D::class, $oClone->getView3D());
     }
 
     public function testDisplayBlankAs(): void
     {
         $object = new Chart();
 
-        $this->assertEquals(Chart::BLANKAS_ZERO, $object->getDisplayBlankAs());
-        $this->assertInstanceOf(Chart::class, $object->setDisplayBlankAs(Chart::BLANKAS_GAP));
-        $this->assertEquals(Chart::BLANKAS_GAP, $object->getDisplayBlankAs());
-        $this->assertInstanceOf(Chart::class, $object->setDisplayBlankAs(Chart::BLANKAS_ZERO));
-        $this->assertEquals(Chart::BLANKAS_ZERO, $object->getDisplayBlankAs());
-        $this->assertInstanceOf(Chart::class, $object->setDisplayBlankAs(Chart::BLANKAS_SPAN));
-        $this->assertEquals(Chart::BLANKAS_SPAN, $object->getDisplayBlankAs());
-        $this->assertInstanceOf(Chart::class, $object->setDisplayBlankAs('Unauthorized value'));
-        $this->assertEquals(Chart::BLANKAS_SPAN, $object->getDisplayBlankAs());
+        self::assertEquals(Chart::BLANKAS_ZERO, $object->getDisplayBlankAs());
+        self::assertInstanceOf(Chart::class, $object->setDisplayBlankAs(Chart::BLANKAS_GAP));
+        self::assertEquals(Chart::BLANKAS_GAP, $object->getDisplayBlankAs());
+        self::assertInstanceOf(Chart::class, $object->setDisplayBlankAs(Chart::BLANKAS_ZERO));
+        self::assertEquals(Chart::BLANKAS_ZERO, $object->getDisplayBlankAs());
+        self::assertInstanceOf(Chart::class, $object->setDisplayBlankAs(Chart::BLANKAS_SPAN));
+        self::assertEquals(Chart::BLANKAS_SPAN, $object->getDisplayBlankAs());
+        self::assertInstanceOf(Chart::class, $object->setDisplayBlankAs('Unauthorized value'));
+        self::assertEquals(Chart::BLANKAS_SPAN, $object->getDisplayBlankAs());
     }
 
     public function testIncludeSpreadsheet(): void
     {
         $object = new Chart();
 
-        $this->assertFalse($object->hasIncludedSpreadsheet());
-        $this->assertInstanceOf(Chart::class, $object->setIncludeSpreadsheet());
-        $this->assertFalse($object->hasIncludedSpreadsheet());
-        $this->assertInstanceOf(Chart::class, $object->setIncludeSpreadsheet(false));
-        $this->assertFalse($object->hasIncludedSpreadsheet());
-        $this->assertInstanceOf(Chart::class, $object->setIncludeSpreadsheet(true));
-        $this->assertTrue($object->hasIncludedSpreadsheet());
+        self::assertFalse($object->hasIncludedSpreadsheet());
+        self::assertInstanceOf(Chart::class, $object->setIncludeSpreadsheet());
+        self::assertFalse($object->hasIncludedSpreadsheet());
+        self::assertInstanceOf(Chart::class, $object->setIncludeSpreadsheet(false));
+        self::assertFalse($object->hasIncludedSpreadsheet());
+        self::assertInstanceOf(Chart::class, $object->setIncludeSpreadsheet(true));
+        self::assertTrue($object->hasIncludedSpreadsheet());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Comment/AuthorTest.php b/tests/PhpPresentation/Tests/Shape/Comment/AuthorTest.php
index e705542467..202275113e 100644
--- a/tests/PhpPresentation/Tests/Shape/Comment/AuthorTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Comment/AuthorTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -34,9 +33,9 @@ public function testConstruct(): void
     {
         $object = new Author();
 
-        $this->assertNull($object->getName());
-        $this->assertNull($object->getIndex());
-        $this->assertNull($object->getInitials());
+        self::assertNull($object->getName());
+        self::assertNull($object->getIndex());
+        self::assertNull($object->getInitials());
     }
 
     public function testGetSetIndex(): void
@@ -44,9 +43,9 @@ public function testGetSetIndex(): void
         $expectedVal = mt_rand(1, 100);
 
         $object = new Author();
-        $this->assertNull($object->getIndex());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Comment\\Author', $object->setIndex($expectedVal));
-        $this->assertEquals($expectedVal, $object->getIndex());
+        self::assertNull($object->getIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Comment\\Author', $object->setIndex($expectedVal));
+        self::assertEquals($expectedVal, $object->getIndex());
     }
 
     public function testGetSetInitials(): void
@@ -54,9 +53,9 @@ public function testGetSetInitials(): void
         $expectedVal = 'AABBCCDD';
 
         $object = new Author();
-        $this->assertNull($object->getInitials());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Comment\\Author', $object->setInitials($expectedVal));
-        $this->assertEquals($expectedVal, $object->getInitials());
+        self::assertNull($object->getInitials());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Comment\\Author', $object->setInitials($expectedVal));
+        self::assertEquals($expectedVal, $object->getInitials());
     }
 
     public function testGetSetName(): void
@@ -64,8 +63,8 @@ public function testGetSetName(): void
         $expectedVal = 'AABBCCDD';
 
         $object = new Author();
-        $this->assertNull($object->getName());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Comment\\Author', $object->setName($expectedVal));
-        $this->assertEquals($expectedVal, $object->getName());
+        self::assertNull($object->getName());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Comment\\Author', $object->setName($expectedVal));
+        self::assertEquals($expectedVal, $object->getName());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/CommentTest.php b/tests/PhpPresentation/Tests/Shape/CommentTest.php
index b1c3490e7d..37d7dd708f 100644
--- a/tests/PhpPresentation/Tests/Shape/CommentTest.php
+++ b/tests/PhpPresentation/Tests/Shape/CommentTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,11 +34,11 @@ public function testConstruct(): void
     {
         $object = new Comment();
 
-        $this->assertNull($object->getAuthor());
-        $this->assertNull($object->getText());
-        $this->assertIsInt($object->getDate());
-        $this->assertNull($object->getHeight());
-        $this->assertNull($object->getWidth());
+        self::assertNull($object->getAuthor());
+        self::assertNull($object->getText());
+        self::assertIsInt($object->getDate());
+        self::assertNull($object->getHeight());
+        self::assertNull($object->getWidth());
     }
 
     public function testGetSetAuthor(): void
@@ -49,9 +48,9 @@ public function testGetSetAuthor(): void
         /** @var Author $oStub */
         $oStub = $this->getMockBuilder(Author::class)->getMock();
 
-        $this->assertNull($object->getAuthor());
-        $this->assertInstanceOf(Comment::class, $object->setAuthor($oStub));
-        $this->assertInstanceOf(Author::class, $object->getAuthor());
+        self::assertNull($object->getAuthor());
+        self::assertInstanceOf(Comment::class, $object->setAuthor($oStub));
+        self::assertInstanceOf(Author::class, $object->getAuthor());
     }
 
     public function testGetSetDate(): void
@@ -59,10 +58,10 @@ public function testGetSetDate(): void
         $expectedDate = time();
 
         $object = new Comment();
-        $this->assertIsInt($object->getDate());
-        $this->assertInstanceOf(Comment::class, $object->setDate($expectedDate));
-        $this->assertEquals($expectedDate, $object->getDate());
-        $this->assertIsInt($object->getDate());
+        self::assertIsInt($object->getDate());
+        self::assertInstanceOf(Comment::class, $object->setDate($expectedDate));
+        self::assertEquals($expectedDate, $object->getDate());
+        self::assertIsInt($object->getDate());
     }
 
     public function testGetSetText(): void
@@ -70,19 +69,19 @@ public function testGetSetText(): void
         $expectedText = 'AABBCCDD';
 
         $object = new Comment();
-        $this->assertNull($object->getText());
-        $this->assertInstanceOf(Comment::class, $object->setText($expectedText));
-        $this->assertEquals($expectedText, $object->getText());
+        self::assertNull($object->getText());
+        self::assertInstanceOf(Comment::class, $object->setText($expectedText));
+        self::assertEquals($expectedText, $object->getText());
     }
 
     public function testGetSetHeightAndWidtg(): void
     {
         $object = new Comment();
-        $this->assertNull($object->getHeight());
-        $this->assertNull($object->getWidth());
-        $this->assertInstanceOf(Comment::class, $object->setHeight(1));
-        $this->assertInstanceOf(Comment::class, $object->setWidth(1));
-        $this->assertNull($object->getHeight());
-        $this->assertNull($object->getWidth());
+        self::assertNull($object->getHeight());
+        self::assertNull($object->getWidth());
+        self::assertInstanceOf(Comment::class, $object->setHeight(1));
+        self::assertInstanceOf(Comment::class, $object->setWidth(1));
+        self::assertNull($object->getHeight());
+        self::assertNull($object->getWidth());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Drawing/Base64Test.php b/tests/PhpPresentation/Tests/Shape/Drawing/Base64Test.php
index c73b8af448..515f4c12a7 100644
--- a/tests/PhpPresentation/Tests/Shape/Drawing/Base64Test.php
+++ b/tests/PhpPresentation/Tests/Shape/Drawing/Base64Test.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -50,16 +49,16 @@ public function testData(): void
     {
         $oDrawing = new Base64();
 
-        $this->assertEmpty($oDrawing->getData());
+        self::assertEmpty($oDrawing->getData());
         $oDrawing->setData($this->imageDataPNG);
-        $this->assertNotEmpty($oDrawing->getData());
+        self::assertNotEmpty($oDrawing->getData());
     }
 
     public function testExtension(): void
     {
         $oDrawing = new Base64();
         $oDrawing->setData($this->imageDataPNG);
-        $this->assertEquals('jpg', $oDrawing->getExtension());
+        self::assertEquals('jpg', $oDrawing->getExtension());
     }
 
     public function testExtensionException(): void
@@ -78,20 +77,20 @@ public function testMimeType(): void
     {
         $oDrawing = new Base64();
         $oDrawing->setData($this->imageDataPNG);
-        $this->assertEquals('image/jpeg', $oDrawing->getMimeType());
+        self::assertEquals('image/jpeg', $oDrawing->getMimeType());
     }
 
     public function testMimeTypeSVG(): void
     {
         $oDrawing = new Base64();
         $oDrawing->setData($this->imageDataSVG);
-        $this->assertEquals('image/svg+xml', $oDrawing->getMimeType());
+        self::assertEquals('image/svg+xml', $oDrawing->getMimeType());
     }
 
     public function testMimeTypeFunctionNotExists(): void
     {
         $oDrawing = new Base64();
         $oDrawing->setData($this->imageDataPNG);
-        $this->assertEquals('image/jpeg', $oDrawing->getMimeType());
+        self::assertEquals('image/jpeg', $oDrawing->getMimeType());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Drawing/FileTest.php b/tests/PhpPresentation/Tests/Shape/Drawing/FileTest.php
index 479f64c1a6..3c7a3f55ef 100644
--- a/tests/PhpPresentation/Tests/Shape/Drawing/FileTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Drawing/FileTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -34,7 +33,7 @@ class FileTest extends TestCase
     public function testConstruct(): void
     {
         $object = new File();
-        $this->assertEmpty($object->getPath());
+        self::assertEmpty($object->getPath());
     }
 
     public function testPathBasic(): void
@@ -43,15 +42,15 @@ public function testPathBasic(): void
         $this->expectExceptionMessage('The file "" doesn\'t exist');
 
         $object = new File();
-        $this->assertInstanceOf(File::class, $object->setPath());
+        self::assertInstanceOf(File::class, $object->setPath());
     }
 
     public function testPathWithoutVerifyFile(): void
     {
         $object = new File();
 
-        $this->assertInstanceOf(File::class, $object->setPath('', false));
-        $this->assertEmpty($object->getPath());
+        self::assertInstanceOf(File::class, $object->setPath('', false));
+        self::assertEmpty($object->getPath());
     }
 
     public function testPathWithRealFile(): void
@@ -60,10 +59,10 @@ public function testPathWithRealFile(): void
 
         $imagePath = dirname(__DIR__, 4) . '/resources/images/PhpPresentationLogo.png';
 
-        $this->assertInstanceOf(File::class, $object->setPath($imagePath, false));
-        $this->assertEquals($imagePath, $object->getPath());
-        $this->assertEquals(0, $object->getWidth());
-        $this->assertEquals(0, $object->getHeight());
+        self::assertInstanceOf(File::class, $object->setPath($imagePath, false));
+        self::assertEquals($imagePath, $object->getPath());
+        self::assertEquals(0, $object->getWidth());
+        self::assertEquals(0, $object->getHeight());
     }
 
     /**
@@ -72,8 +71,8 @@ public function testPathWithRealFile(): void
     public function testMimeType(string $pathFile, string $mimeType): void
     {
         $object = new File();
-        $this->assertInstanceOf(File::class, $object->setPath($pathFile));
-        $this->assertEquals($mimeType, $object->getMimeType());
+        self::assertInstanceOf(File::class, $object->setPath($pathFile));
+        self::assertEquals($mimeType, $object->getMimeType());
     }
 
     /**
diff --git a/tests/PhpPresentation/Tests/Shape/Drawing/ZipFileTest.php b/tests/PhpPresentation/Tests/Shape/Drawing/ZipFileTest.php
index 3a5a7fbb25..bd35ac9c72 100644
--- a/tests/PhpPresentation/Tests/Shape/Drawing/ZipFileTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Drawing/ZipFileTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -72,13 +71,13 @@ public function testExtension(): void
     {
         $oDrawing = new ZipFile();
         $oDrawing->setPath($this->fileOk);
-        $this->assertEquals('gif', $oDrawing->getExtension());
+        self::assertEquals('gif', $oDrawing->getExtension());
     }
 
     public function testMimeType(): void
     {
         $oDrawing = new ZipFile();
         $oDrawing->setPath($this->fileOk);
-        $this->assertEquals('image/gif', $oDrawing->getMimeType());
+        self::assertEquals('image/gif', $oDrawing->getMimeType());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/GroupTest.php b/tests/PhpPresentation/Tests/Shape/GroupTest.php
index 85cb4cd607..93cbbf7d79 100644
--- a/tests/PhpPresentation/Tests/Shape/GroupTest.php
+++ b/tests/PhpPresentation/Tests/Shape/GroupTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,25 +34,25 @@ public function testConstruct(): void
     {
         $object = new Group();
 
-        $this->assertEquals(0, $object->getOffsetX());
-        $this->assertEquals(0, $object->getOffsetY());
-        $this->assertEquals(0, $object->getExtentX());
-        $this->assertEquals(0, $object->getExtentY());
-        $this->assertEquals(0, $object->getShapeCollection()->count());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->setWidth(rand(1, 100)));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->setHeight(rand(1, 100)));
+        self::assertEquals(0, $object->getOffsetX());
+        self::assertEquals(0, $object->getOffsetY());
+        self::assertEquals(0, $object->getExtentX());
+        self::assertEquals(0, $object->getExtentY());
+        self::assertEquals(0, $object->getShapeCollection()->count());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->setWidth(mt_rand(1, 100)));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->setHeight(mt_rand(1, 100)));
     }
 
     public function testAdd(): void
     {
         $object = new Group();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart', $object->createChartShape());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Drawing\\File', $object->createDrawingShape());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Line', $object->createLineShape(10, 10, 10, 10));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText', $object->createRichTextShape());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table', $object->createTableShape());
-        $this->assertEquals(5, $object->getShapeCollection()->count());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart', $object->createChartShape());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Drawing\\File', $object->createDrawingShape());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Line', $object->createLineShape(10, 10, 10, 10));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText', $object->createRichTextShape());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table', $object->createTableShape());
+        self::assertEquals(5, $object->getShapeCollection()->count());
     }
 
     public function testExtentX(): void
@@ -62,7 +61,7 @@ public function testExtentX(): void
         $line1 = new Line(10, 20, 30, 50);
         $object->addShape($line1);
 
-        $this->assertEquals(20, $object->getExtentX());
+        self::assertEquals(20, $object->getExtentX());
     }
 
     public function testExtentY(): void
@@ -71,7 +70,7 @@ public function testExtentY(): void
         $line1 = new Line(10, 20, 30, 50);
         $object->addShape($line1);
 
-        $this->assertEquals(30, $object->getExtentY());
+        self::assertEquals(30, $object->getExtentY());
     }
 
     public function testOffsetX(): void
@@ -80,10 +79,10 @@ public function testOffsetX(): void
         $line1 = new Line(10, 20, 30, 50);
         $object->addShape($line1);
 
-        $this->assertEquals(10, $object->getOffsetX());
+        self::assertEquals(10, $object->getOffsetX());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->setOffsetX(rand(1, 100)));
-        $this->assertEquals(10, $object->getOffsetX());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->setOffsetX(mt_rand(1, 100)));
+        self::assertEquals(10, $object->getOffsetX());
     }
 
     public function testOffsetY(): void
@@ -92,10 +91,10 @@ public function testOffsetY(): void
         $line1 = new Line(10, 20, 30, 50);
         $object->addShape($line1);
 
-        $this->assertEquals(20, $object->getOffsetY());
+        self::assertEquals(20, $object->getOffsetY());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->setOffsetY(rand(1, 100)));
-        $this->assertEquals(20, $object->getOffsetY());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->setOffsetY(mt_rand(1, 100)));
+        self::assertEquals(20, $object->getOffsetY());
     }
 
     public function testExtentsAndOffsetsForOneShape(): void
@@ -114,10 +113,10 @@ public function testExtentsAndOffsetsForOneShape(): void
         $line1 = new Line($offsetX, $offsetY, $endX, $endY);
         $object->addShape($line1);
 
-        $this->assertEquals($offsetX, $object->getOffsetX());
-        $this->assertEquals($offsetY, $object->getOffsetY());
-        $this->assertEquals($extentX, $object->getExtentX());
-        $this->assertEquals($extentY, $object->getExtentY());
+        self::assertEquals($offsetX, $object->getOffsetX());
+        self::assertEquals($offsetY, $object->getOffsetY());
+        self::assertEquals($extentX, $object->getExtentX());
+        self::assertEquals($extentY, $object->getExtentY());
     }
 
     public function testExtentsAndOffsetsForTwoShapes(): void
@@ -147,9 +146,9 @@ public function testExtentsAndOffsetsForTwoShapes(): void
         $object->addShape($line1);
         $object->addShape($line2);
 
-        $this->assertEquals($offsetX, $object->getOffsetX());
-        $this->assertEquals($offsetY, $object->getOffsetY());
-        $this->assertEquals($extentX, $object->getExtentX());
-        $this->assertEquals($extentY, $object->getExtentY());
+        self::assertEquals($offsetX, $object->getOffsetX());
+        self::assertEquals($offsetY, $object->getOffsetY());
+        self::assertEquals($extentX, $object->getExtentX());
+        self::assertEquals($extentY, $object->getExtentY());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/HyperlinkTest.php b/tests/PhpPresentation/Tests/Shape/HyperlinkTest.php
index 0b027e1401..1b79991c18 100644
--- a/tests/PhpPresentation/Tests/Shape/HyperlinkTest.php
+++ b/tests/PhpPresentation/Tests/Shape/HyperlinkTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,16 +35,16 @@ class HyperlinkTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Hyperlink();
-        $this->assertEmpty($object->getUrl());
-        $this->assertEmpty($object->getTooltip());
+        self::assertEmpty($object->getUrl());
+        self::assertEmpty($object->getTooltip());
 
         $object = new Hyperlink('http://test.com');
-        $this->assertEquals('http://test.com', $object->getUrl());
-        $this->assertEmpty($object->getTooltip());
+        self::assertEquals('http://test.com', $object->getUrl());
+        self::assertEmpty($object->getTooltip());
 
         $object = new Hyperlink('http://test.com', 'Test');
-        $this->assertEquals('http://test.com', $object->getUrl());
-        $this->assertEquals('Test', $object->getTooltip());
+        self::assertEquals('http://test.com', $object->getUrl());
+        self::assertEquals('Test', $object->getTooltip());
     }
 
     /**
@@ -54,13 +53,13 @@ public function testConstruct(): void
     public function testGetHashCode(): void
     {
         $object = new Hyperlink();
-        $this->assertEquals(md5(get_class($object)), $object->getHashCode());
+        self::assertEquals(md5(get_class($object)), $object->getHashCode());
 
         $object = new Hyperlink('http://test.com');
-        $this->assertEquals(md5('http://test.com' . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5('http://test.com' . get_class($object)), $object->getHashCode());
 
         $object = new Hyperlink('http://test.com', 'Test');
-        $this->assertEquals(md5('http://test.com' . 'Test' . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5('http://test.com' . 'Test' . get_class($object)), $object->getHashCode());
     }
 
     /**
@@ -71,66 +70,66 @@ public function testSetGetHashIndex(): void
         $object = new Hyperlink();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testGetSetSlideNumber(): void
     {
         $object = new Hyperlink();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setSlideNumber());
-        $this->assertEquals(1, $object->getSlideNumber());
-        $this->assertEquals('ppaction://hlinksldjump', $object->getUrl());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setSlideNumber());
+        self::assertEquals(1, $object->getSlideNumber());
+        self::assertEquals('ppaction://hlinksldjump', $object->getUrl());
 
         $value = mt_rand(1, 100);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setSlideNumber($value));
-        $this->assertEquals($value, $object->getSlideNumber());
-        $this->assertEquals('ppaction://hlinksldjump', $object->getUrl());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setSlideNumber($value));
+        self::assertEquals($value, $object->getSlideNumber());
+        self::assertEquals('ppaction://hlinksldjump', $object->getUrl());
     }
 
     public function testGetSetTooltip(): void
     {
         $object = new Hyperlink();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setTooltip());
-        $this->assertEmpty($object->getTooltip());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setTooltip());
+        self::assertEmpty($object->getTooltip());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setTooltip('TEST'));
-        $this->assertEquals('TEST', $object->getTooltip());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setTooltip('TEST'));
+        self::assertEquals('TEST', $object->getTooltip());
     }
 
     public function testGetSetUrl(): void
     {
         $object = new Hyperlink();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setUrl());
-        $this->assertEmpty($object->getUrl());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setUrl());
+        self::assertEmpty($object->getUrl());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setUrl('http://www.github.com'));
-        $this->assertEquals('http://www.github.com', $object->getUrl());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setUrl('http://www.github.com'));
+        self::assertEquals('http://www.github.com', $object->getUrl());
     }
 
     public function testIsInternal(): void
     {
         $object = new Hyperlink();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setSlideNumber());
-        $this->assertTrue($object->isInternal());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setSlideNumber());
+        self::assertTrue($object->isInternal());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setUrl('http://www.github.com'));
-        $this->assertFalse($object->isInternal());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setUrl('http://www.github.com'));
+        self::assertFalse($object->isInternal());
     }
 
     public function testIsTextColorUsed(): void
     {
         $object = new Hyperlink();
-        $this->assertFalse($object->isTextColorUsed());
+        self::assertFalse($object->isTextColorUsed());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setIsTextColorUsed(true));
-        $this->assertTrue($object->isTextColorUsed());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setIsTextColorUsed(true));
+        self::assertTrue($object->isTextColorUsed());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setIsTextColorUsed(false));
-        $this->assertFalse($object->isTextColorUsed());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->setIsTextColorUsed(false));
+        self::assertFalse($object->isTextColorUsed());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/LineTest.php b/tests/PhpPresentation/Tests/Shape/LineTest.php
index 12ada15315..4bbfeecd9a 100644
--- a/tests/PhpPresentation/Tests/Shape/LineTest.php
+++ b/tests/PhpPresentation/Tests/Shape/LineTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -39,11 +38,11 @@ public function testConstruct(): void
         $value = mt_rand(1, 100);
         $object = new Line($value, $value, $value, $value);
 
-        $this->assertEquals(Border::LINE_SINGLE, $object->getBorder()->getLineStyle());
-        $this->assertEquals($value, $object->getOffsetX());
-        $this->assertEquals($value, $object->getOffsetY());
-        $this->assertEquals(0, $object->getWidth());
-        $this->assertEquals(0, $object->getHeight());
-        $this->assertIsString($object->getHashCode());
+        self::assertEquals(Border::LINE_SINGLE, $object->getBorder()->getLineStyle());
+        self::assertEquals($value, $object->getOffsetX());
+        self::assertEquals($value, $object->getOffsetY());
+        self::assertEquals(0, $object->getWidth());
+        self::assertEquals(0, $object->getHeight());
+        self::assertIsString($object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/MediaTest.php b/tests/PhpPresentation/Tests/Shape/MediaTest.php
index 14508464c6..cd6e6502ba 100644
--- a/tests/PhpPresentation/Tests/Shape/MediaTest.php
+++ b/tests/PhpPresentation/Tests/Shape/MediaTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -29,19 +28,19 @@ public function testInheritance(): void
     {
         $object = new Media();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Drawing\\File', $object);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Drawing\\File', $object);
     }
 
     public function testMimeType(): void
     {
         $object = new Media();
         $object->setPath('file.mp4', false);
-        $this->assertEquals('video/mp4', $object->getMimeType());
+        self::assertEquals('video/mp4', $object->getMimeType());
         $object->setPath('file.ogv', false);
-        $this->assertEquals('video/ogg', $object->getMimeType());
+        self::assertEquals('video/ogg', $object->getMimeType());
         $object->setPath('file.wmv', false);
-        $this->assertEquals('video/x-ms-wmv', $object->getMimeType());
+        self::assertEquals('video/x-ms-wmv', $object->getMimeType());
         $object->setPath('file.xxx', false);
-        $this->assertEquals('application/octet-stream', $object->getMimeType());
+        self::assertEquals('application/octet-stream', $object->getMimeType());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/PlaceholderTest.php b/tests/PhpPresentation/Tests/Shape/PlaceholderTest.php
index eb741d24f3..bdc81e7775 100644
--- a/tests/PhpPresentation/Tests/Shape/PlaceholderTest.php
+++ b/tests/PhpPresentation/Tests/Shape/PlaceholderTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -22,6 +21,7 @@
 
 use PhpOffice\PhpPresentation\Shape\Placeholder;
 use PHPUnit\Framework\TestCase;
+use ReflectionClass;
 
 /**
  * Test class for Table element.
@@ -33,8 +33,8 @@ class PlaceholderTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Placeholder(Placeholder::PH_TYPE_BODY);
-        $this->assertEquals(Placeholder::PH_TYPE_BODY, $object->getType());
-        $this->assertNull($object->getIdx());
+        self::assertEquals(Placeholder::PH_TYPE_BODY, $object->getType());
+        self::assertNull($object->getIdx());
     }
 
     public function testIdx(): void
@@ -42,20 +42,20 @@ public function testIdx(): void
         $value = mt_rand(0, 100);
 
         $object = new Placeholder(Placeholder::PH_TYPE_BODY);
-        $this->assertNull($object->getIdx());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Placeholder', $object->setIdx($value));
-        $this->assertEquals($value, $object->getIdx());
+        self::assertNull($object->getIdx());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Placeholder', $object->setIdx($value));
+        self::assertEquals($value, $object->getIdx());
     }
 
     public function testType(): void
     {
-        $rcPlaceholder = new \ReflectionClass('PhpOffice\PhpPresentation\Shape\Placeholder');
+        $rcPlaceholder = new ReflectionClass('PhpOffice\PhpPresentation\Shape\Placeholder');
         $arrayConstants = $rcPlaceholder->getConstants();
         $value = array_rand($arrayConstants);
 
         $object = new Placeholder(Placeholder::PH_TYPE_BODY);
-        $this->assertEquals(Placeholder::PH_TYPE_BODY, $object->getType());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Placeholder', $object->setType($value));
-        $this->assertEquals($value, $object->getType());
+        self::assertEquals(Placeholder::PH_TYPE_BODY, $object->getType());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Placeholder', $object->setType($value));
+        self::assertEquals($value, $object->getType());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/RichText/BreakElementTest.php b/tests/PhpPresentation/Tests/Shape/RichText/BreakElementTest.php
index 512af22a9d..085d7aadf0 100644
--- a/tests/PhpPresentation/Tests/Shape/RichText/BreakElementTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichText/BreakElementTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,25 +35,25 @@ class BreakElementTest extends TestCase
     public function testText(): void
     {
         $object = new BreakElement();
-        $this->assertEquals("\r\n", $object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->setText());
-        $this->assertEquals("\r\n", $object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->setText('AAA'));
-        $this->assertEquals("\r\n", $object->getText());
+        self::assertEquals("\r\n", $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->setText());
+        self::assertEquals("\r\n", $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->setText('AAA'));
+        self::assertEquals("\r\n", $object->getText());
     }
 
     public function testFont(): void
     {
         $object = new BreakElement();
-        $this->assertNull($object->getFont());
+        self::assertNull($object->getFont());
     }
 
     public function testLanguage(): void
     {
         $object = new BreakElement();
-        $this->assertNull($object->getLanguage());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->setLanguage('en-US'));
-        $this->assertNull($object->getLanguage());
+        self::assertNull($object->getLanguage());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->setLanguage('en-US'));
+        self::assertNull($object->getLanguage());
     }
 
     /**
@@ -63,6 +62,6 @@ public function testLanguage(): void
     public function testHashCode(): void
     {
         $object = new BreakElement();
-        $this->assertEquals(md5(get_class($object)), $object->getHashCode());
+        self::assertEquals(md5(get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/RichText/ParagraphTest.php b/tests/PhpPresentation/Tests/Shape/RichText/ParagraphTest.php
index be34b6f1cf..57f9d6fc8b 100644
--- a/tests/PhpPresentation/Tests/Shape/RichText/ParagraphTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichText/ParagraphTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -40,17 +39,17 @@ class ParagraphTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Paragraph();
-        $this->assertEmpty($object->getRichTextElements());
-        $this->assertInstanceOf(Alignment::class, $object->getAlignment());
-        $this->assertInstanceOf(Font::class, $object->getFont());
-        $this->assertInstanceOf(Bullet::class, $object->getBulletStyle());
+        self::assertEmpty($object->getRichTextElements());
+        self::assertInstanceOf(Alignment::class, $object->getAlignment());
+        self::assertInstanceOf(Font::class, $object->getFont());
+        self::assertInstanceOf(Bullet::class, $object->getBulletStyle());
     }
 
     public function testAlignment(): void
     {
         $object = new Paragraph();
-        $this->assertInstanceOf(Alignment::class, $object->getAlignment());
-        $this->assertInstanceOf(Paragraph::class, $object->setAlignment(new Alignment()));
+        self::assertInstanceOf(Alignment::class, $object->getAlignment());
+        self::assertInstanceOf(Paragraph::class, $object->setAlignment(new Alignment()));
     }
 
     /**
@@ -59,11 +58,11 @@ public function testAlignment(): void
     public function testBulletStyle(): void
     {
         $object = new Paragraph();
-        $this->assertInstanceOf(Bullet::class, $object->getBulletStyle());
-        $this->assertInstanceOf(Paragraph::class, $object->setBulletStyle());
-        $this->assertNull($object->getBulletStyle());
-        $this->assertInstanceOf(Paragraph::class, $object->setBulletStyle(new Bullet()));
-        $this->assertInstanceOf(Bullet::class, $object->getBulletStyle());
+        self::assertInstanceOf(Bullet::class, $object->getBulletStyle());
+        self::assertInstanceOf(Paragraph::class, $object->setBulletStyle());
+        self::assertNull($object->getBulletStyle());
+        self::assertInstanceOf(Paragraph::class, $object->setBulletStyle(new Bullet()));
+        self::assertInstanceOf(Bullet::class, $object->getBulletStyle());
     }
 
     /**
@@ -72,11 +71,11 @@ public function testBulletStyle(): void
     public function testFont(): void
     {
         $object = new Paragraph();
-        $this->assertInstanceOf(Font::class, $object->getFont());
-        $this->assertInstanceOf(Paragraph::class, $object->setFont());
-        $this->assertNull($object->getFont());
-        $this->assertInstanceOf(Paragraph::class, $object->setFont(new Font()));
-        $this->assertInstanceOf(Font::class, $object->getFont());
+        self::assertInstanceOf(Font::class, $object->getFont());
+        self::assertInstanceOf(Paragraph::class, $object->setFont());
+        self::assertNull($object->getFont());
+        self::assertInstanceOf(Paragraph::class, $object->setFont(new Font()));
+        self::assertInstanceOf(Font::class, $object->getFont());
     }
 
     /**
@@ -87,7 +86,7 @@ public function testHashCode(): void
         $object = new Paragraph();
         $oElement = new TextElement();
         $object->addText($oElement);
-        $this->assertEquals(md5($oElement->getHashCode() . $object->getFont()->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($oElement->getHashCode() . $object->getFont()->getHashCode() . get_class($object)), $object->getHashCode());
     }
 
     /**
@@ -98,7 +97,7 @@ public function testHashIndex(): void
         $object = new Paragraph();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     /**
@@ -108,9 +107,9 @@ public function testLineSpacing(): void
     {
         $object = new Paragraph();
         $valueExpected = mt_rand(1, 100);
-        $this->assertEquals(100, $object->getLineSpacing());
-        $this->assertInstanceOf(Paragraph::class, $object->setLineSpacing($valueExpected));
-        $this->assertEquals($valueExpected, $object->getLineSpacing());
+        self::assertEquals(100, $object->getLineSpacing());
+        self::assertInstanceOf(Paragraph::class, $object->setLineSpacing($valueExpected));
+        self::assertEquals($valueExpected, $object->getLineSpacing());
     }
 
     /**
@@ -119,13 +118,13 @@ public function testLineSpacing(): void
     public function testLineSpacingMode(): void
     {
         $object = new Paragraph();
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $object->getLineSpacingMode());
-        $this->assertInstanceOf(Paragraph::class, $object->setLineSpacingMode(Paragraph::LINE_SPACING_MODE_POINT));
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_POINT, $object->getLineSpacingMode());
-        $this->assertInstanceOf(Paragraph::class, $object->setLineSpacingMode(Paragraph::LINE_SPACING_MODE_PERCENT));
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $object->getLineSpacingMode());
-        $this->assertInstanceOf(Paragraph::class, $object->setLineSpacingMode('Unauthorized'));
-        $this->assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $object->getLineSpacingMode());
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $object->getLineSpacingMode());
+        self::assertInstanceOf(Paragraph::class, $object->setLineSpacingMode(Paragraph::LINE_SPACING_MODE_POINT));
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_POINT, $object->getLineSpacingMode());
+        self::assertInstanceOf(Paragraph::class, $object->setLineSpacingMode(Paragraph::LINE_SPACING_MODE_PERCENT));
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $object->getLineSpacingMode());
+        self::assertInstanceOf(Paragraph::class, $object->setLineSpacingMode('Unauthorized'));
+        self::assertEquals(Paragraph::LINE_SPACING_MODE_PERCENT, $object->getLineSpacingMode());
     }
 
     /**
@@ -134,34 +133,34 @@ public function testLineSpacingMode(): void
     public function testRichTextElements(): void
     {
         $object = new Paragraph();
-        $this->assertIsArray($object->getRichTextElements());
-        $this->assertEmpty($object->getRichTextElements());
+        self::assertIsArray($object->getRichTextElements());
+        self::assertEmpty($object->getRichTextElements());
         $object->createBreak();
-        $this->assertCount(1, $object->getRichTextElements());
+        self::assertCount(1, $object->getRichTextElements());
 
         $array = [
             new TextElement(),
             new TextElement(),
             new TextElement(),
         ];
-        $this->assertInstanceOf(Paragraph::class, $object->setRichTextElements($array));
-        $this->assertCount(3, $object->getRichTextElements());
+        self::assertInstanceOf(Paragraph::class, $object->setRichTextElements($array));
+        self::assertCount(3, $object->getRichTextElements());
     }
 
     public function testSpacingAfter(): void
     {
         $object = new Paragraph();
-        $this->assertEquals(0, $object->getSpacingAfter());
-        $this->assertInstanceOf(Paragraph::class, $object->setSpacingAfter(1));
-        $this->assertEquals(1, $object->getSpacingAfter());
+        self::assertEquals(0, $object->getSpacingAfter());
+        self::assertInstanceOf(Paragraph::class, $object->setSpacingAfter(1));
+        self::assertEquals(1, $object->getSpacingAfter());
     }
 
     public function testSpacingBefore(): void
     {
         $object = new Paragraph();
-        $this->assertEquals(0, $object->getSpacingBefore());
-        $this->assertInstanceOf(Paragraph::class, $object->setSpacingBefore(1));
-        $this->assertEquals(1, $object->getSpacingBefore());
+        self::assertEquals(0, $object->getSpacingBefore());
+        self::assertInstanceOf(Paragraph::class, $object->setSpacingBefore(1));
+        self::assertEquals(1, $object->getSpacingBefore());
     }
 
     /**
@@ -170,19 +169,19 @@ public function testSpacingBefore(): void
     public function testText(): void
     {
         $object = new Paragraph();
-        $this->assertInstanceOf(Paragraph::class, $object->addText(new TextElement()));
-        $this->assertCount(1, $object->getRichTextElements());
-        $this->assertInstanceOf(TextElement::class, $object->createText());
-        $this->assertCount(2, $object->getRichTextElements());
-        $this->assertInstanceOf(TextElement::class, $object->createText('AAA'));
-        $this->assertCount(3, $object->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->createBreak());
-        $this->assertCount(4, $object->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->createTextRun());
-        $this->assertCount(5, $object->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->createTextRun('BBB'));
-        $this->assertCount(6, $object->getRichTextElements());
-        $this->assertEquals('AAA' . "\r\n" . 'BBB', $object->getPlainText());
-        $this->assertEquals('AAA' . "\r\n" . 'BBB', (string) $object);
+        self::assertInstanceOf(Paragraph::class, $object->addText(new TextElement()));
+        self::assertCount(1, $object->getRichTextElements());
+        self::assertInstanceOf(TextElement::class, $object->createText());
+        self::assertCount(2, $object->getRichTextElements());
+        self::assertInstanceOf(TextElement::class, $object->createText('AAA'));
+        self::assertCount(3, $object->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->createBreak());
+        self::assertCount(4, $object->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->createTextRun());
+        self::assertCount(5, $object->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->createTextRun('BBB'));
+        self::assertCount(6, $object->getRichTextElements());
+        self::assertEquals('AAA' . "\r\n" . 'BBB', $object->getPlainText());
+        self::assertEquals('AAA' . "\r\n" . 'BBB', (string) $object);
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/RichText/RunTest.php b/tests/PhpPresentation/Tests/Shape/RichText/RunTest.php
index 0deb0b3336..213bb2982f 100644
--- a/tests/PhpPresentation/Tests/Shape/RichText/RunTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichText/RunTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,40 +36,40 @@ class RunTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Run();
-        $this->assertEquals('', $object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
+        self::assertEquals('', $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
 
         $object = new Run('BBB');
-        $this->assertEquals('BBB', $object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
+        self::assertEquals('BBB', $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
     }
 
     public function testFont(): void
     {
         $object = new Run();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->setFont(new Font()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->setFont(new Font()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Font', $object->getFont());
     }
 
     public function testLanguage(): void
     {
         $object = new Run();
-        $this->assertNull($object->getLanguage());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->setLanguage('en-US'));
-        $this->assertEquals('en-US', $object->getLanguage());
+        self::assertNull($object->getLanguage());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->setLanguage('en-US'));
+        self::assertEquals('en-US', $object->getLanguage());
     }
 
     public function testText(): void
     {
         $object = new Run();
-        $this->assertEquals('', $object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->setText());
-        $this->assertEquals('', $object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->setText('AAA'));
-        $this->assertEquals('AAA', $object->getText());
+        self::assertEquals('', $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->setText());
+        self::assertEquals('', $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->setText('AAA'));
+        self::assertEquals('AAA', $object->getText());
 
         $object = new Run('BBB');
-        $this->assertEquals('BBB', $object->getText());
+        self::assertEquals('BBB', $object->getText());
     }
 
     /**
@@ -79,6 +78,6 @@ public function testText(): void
     public function testHashCode(): void
     {
         $object = new Run();
-        $this->assertEquals(md5($object->getFont()->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($object->getFont()->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/RichText/TextElementTest.php b/tests/PhpPresentation/Tests/Shape/RichText/TextElementTest.php
index f63de69d45..0a0eb7f146 100644
--- a/tests/PhpPresentation/Tests/Shape/RichText/TextElementTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichText/TextElementTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,47 +36,47 @@ class TextElementTest extends TestCase
     public function testConstruct(): void
     {
         $object = new TextElement();
-        $this->assertEquals('', $object->getText());
+        self::assertEquals('', $object->getText());
 
         $object = new TextElement('AAA');
-        $this->assertEquals('AAA', $object->getText());
+        self::assertEquals('AAA', $object->getText());
     }
 
     public function testFont(): void
     {
         $object = new TextElement();
-        $this->assertNull($object->getFont());
+        self::assertNull($object->getFont());
     }
 
     public function testHyperlink(): void
     {
         $object = new TextElement();
-        $this->assertFalse($object->hasHyperlink());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setHyperlink());
-        $this->assertFalse($object->hasHyperlink());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->getHyperlink());
-        $this->assertTrue($object->hasHyperlink());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setHyperlink(new Hyperlink('http://www.google.fr')));
-        $this->assertTrue($object->hasHyperlink());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->getHyperlink());
+        self::assertFalse($object->hasHyperlink());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setHyperlink());
+        self::assertFalse($object->hasHyperlink());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->getHyperlink());
+        self::assertTrue($object->hasHyperlink());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setHyperlink(new Hyperlink('http://www.google.fr')));
+        self::assertTrue($object->hasHyperlink());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Hyperlink', $object->getHyperlink());
     }
 
     public function testLanguage(): void
     {
         $object = new TextElement();
-        $this->assertNull($object->getLanguage());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setLanguage('en-US'));
-        $this->assertEquals('en-US', $object->getLanguage());
+        self::assertNull($object->getLanguage());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setLanguage('en-US'));
+        self::assertEquals('en-US', $object->getLanguage());
     }
 
     public function testText(): void
     {
         $object = new TextElement();
-        $this->assertEquals('', $object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setText());
-        $this->assertEquals('', $object->getText());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setText('AAA'));
-        $this->assertEquals('AAA', $object->getText());
+        self::assertEquals('', $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setText());
+        self::assertEquals('', $object->getText());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->setText('AAA'));
+        self::assertEquals('AAA', $object->getText());
     }
 
     /**
@@ -86,6 +85,6 @@ public function testText(): void
     public function testHashCode(): void
     {
         $object = new TextElement();
-        $this->assertEquals(md5(get_class($object)), $object->getHashCode());
+        self::assertEquals(md5(get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/RichTextTest.php b/tests/PhpPresentation/Tests/Shape/RichTextTest.php
index 7019fc292a..4fd6975746 100644
--- a/tests/PhpPresentation/Tests/Shape/RichTextTest.php
+++ b/tests/PhpPresentation/Tests/Shape/RichTextTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -38,23 +37,23 @@ class RichTextTest extends TestCase
     public function testConstruct(): void
     {
         $object = new RichText();
-        $this->assertEquals(0, $object->getActiveParagraphIndex());
-        $this->assertCount(1, $object->getParagraphs());
+        self::assertEquals(0, $object->getActiveParagraphIndex());
+        self::assertCount(1, $object->getParagraphs());
     }
 
     public function testActiveParagraph(): void
     {
         $object = new RichText();
-        $this->assertEquals(0, $object->getActiveParagraphIndex());
-        $this->assertInstanceOf(Paragraph::class, $object->createParagraph());
-        $this->assertCount(2, $object->getParagraphs());
+        self::assertEquals(0, $object->getActiveParagraphIndex());
+        self::assertInstanceOf(Paragraph::class, $object->createParagraph());
+        self::assertCount(2, $object->getParagraphs());
         $value = mt_rand(0, 1);
-        $this->assertInstanceOf(Paragraph::class, $object->setActiveParagraph($value));
-        $this->assertEquals($value, $object->getActiveParagraphIndex());
-        $this->assertInstanceOf(Paragraph::class, $object->getActiveParagraph());
-        $this->assertInstanceOf(Paragraph::class, $object->getParagraph());
+        self::assertInstanceOf(Paragraph::class, $object->setActiveParagraph($value));
+        self::assertEquals($value, $object->getActiveParagraphIndex());
+        self::assertInstanceOf(Paragraph::class, $object->getActiveParagraph());
+        self::assertInstanceOf(Paragraph::class, $object->getParagraph());
         $value = mt_rand(0, 1);
-        $this->assertInstanceOf(Paragraph::class, $object->getParagraph($value));
+        self::assertInstanceOf(Paragraph::class, $object->getParagraph($value));
     }
 
     public function testActiveParagraphException(): void
@@ -80,20 +79,20 @@ public function testColumns(): void
         $object = new RichText();
 
         $value = mt_rand(1, 16);
-        $this->assertInstanceOf(RichText::class, $object->setColumns($value));
-        $this->assertEquals($value, $object->getColumns());
+        self::assertInstanceOf(RichText::class, $object->setColumns($value));
+        self::assertEquals($value, $object->getColumns());
     }
 
     public function testColumnSpacing(): void
     {
         $object = new RichText();
 
-        $this->assertEquals(0, $object->getColumnSpacing());
+        self::assertEquals(0, $object->getColumnSpacing());
         $value = mt_rand(1, 16);
-        $this->assertInstanceOf(RichText::class, $object->setColumnSpacing($value));
-        $this->assertEquals($value, $object->getColumnSpacing());
-        $this->assertInstanceOf(RichText::class, $object->setColumnSpacing(-1));
-        $this->assertEquals($value, $object->getColumnSpacing());
+        self::assertInstanceOf(RichText::class, $object->setColumnSpacing($value));
+        self::assertEquals($value, $object->getColumnSpacing());
+        self::assertInstanceOf(RichText::class, $object->setColumnSpacing(-1));
+        self::assertEquals($value, $object->getColumnSpacing());
     }
 
     public function testColumnsException(): void
@@ -115,86 +114,86 @@ public function testParagraphs(): void
             new Paragraph(),
         ];
 
-        $this->assertInstanceOf(RichText::class, $object->setParagraphs($array));
-        $this->assertCount(3, $object->getParagraphs());
-        $this->assertEquals(2, $object->getActiveParagraphIndex());
+        self::assertInstanceOf(RichText::class, $object->setParagraphs($array));
+        self::assertCount(3, $object->getParagraphs());
+        self::assertEquals(2, $object->getActiveParagraphIndex());
     }
 
     public function testText(): void
     {
         $object = new RichText();
-        $this->assertInstanceOf(RichText::class, $object->addText());
-        $this->assertCount(1, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf(RichText::class, $object->addText(new TextElement()));
-        $this->assertCount(2, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf(TextElement::class, $object->createText());
-        $this->assertCount(3, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf(TextElement::class, $object->createText('ALPHA'));
-        $this->assertCount(4, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf(BreakElement::class, $object->createBreak());
-        $this->assertCount(5, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf(Run::class, $object->createTextRun());
-        $this->assertCount(6, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf(Run::class, $object->createTextRun('BETA'));
-        $this->assertCount(7, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertEquals('ALPHA' . "\r\n" . 'BETA', $object->getPlainText());
-        $this->assertEquals('ALPHA' . "\r\n" . 'BETA', (string) $object);
+        self::assertInstanceOf(RichText::class, $object->addText());
+        self::assertCount(1, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf(RichText::class, $object->addText(new TextElement()));
+        self::assertCount(2, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf(TextElement::class, $object->createText());
+        self::assertCount(3, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf(TextElement::class, $object->createText('ALPHA'));
+        self::assertCount(4, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf(BreakElement::class, $object->createBreak());
+        self::assertCount(5, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf(Run::class, $object->createTextRun());
+        self::assertCount(6, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf(Run::class, $object->createTextRun('BETA'));
+        self::assertCount(7, $object->getActiveParagraph()->getRichTextElements());
+        self::assertEquals('ALPHA' . "\r\n" . 'BETA', $object->getPlainText());
+        self::assertEquals('ALPHA' . "\r\n" . 'BETA', (string) $object);
     }
 
     public function testGetSetAutoFit(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoFit());
-        $this->assertEquals(RichText::AUTOFIT_DEFAULT, $object->getAutoFit());
+        self::assertInstanceOf(RichText::class, $object->setAutoFit());
+        self::assertEquals(RichText::AUTOFIT_DEFAULT, $object->getAutoFit());
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoFit(RichText::AUTOFIT_NORMAL));
-        $this->assertEquals(RichText::AUTOFIT_NORMAL, $object->getAutoFit());
+        self::assertInstanceOf(RichText::class, $object->setAutoFit(RichText::AUTOFIT_NORMAL));
+        self::assertEquals(RichText::AUTOFIT_NORMAL, $object->getAutoFit());
     }
 
     public function testGetSetHAutoShrink(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoShrinkHorizontal());
-        $this->assertNull($object->hasAutoShrinkHorizontal());
+        self::assertInstanceOf(RichText::class, $object->setAutoShrinkHorizontal());
+        self::assertNull($object->hasAutoShrinkHorizontal());
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoShrinkHorizontal(null));
-        $this->assertNull($object->hasAutoShrinkHorizontal());
+        self::assertInstanceOf(RichText::class, $object->setAutoShrinkHorizontal(null));
+        self::assertNull($object->hasAutoShrinkHorizontal());
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoShrinkHorizontal(true));
-        $this->assertTrue($object->hasAutoShrinkHorizontal());
+        self::assertInstanceOf(RichText::class, $object->setAutoShrinkHorizontal(true));
+        self::assertTrue($object->hasAutoShrinkHorizontal());
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoShrinkHorizontal(false));
-        $this->assertFalse($object->hasAutoShrinkHorizontal());
+        self::assertInstanceOf(RichText::class, $object->setAutoShrinkHorizontal(false));
+        self::assertFalse($object->hasAutoShrinkHorizontal());
     }
 
     public function testGetSetVAutoShrink(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoShrinkVertical());
-        $this->assertNull($object->hasAutoShrinkVertical());
+        self::assertInstanceOf(RichText::class, $object->setAutoShrinkVertical());
+        self::assertNull($object->hasAutoShrinkVertical());
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoShrinkVertical(null));
-        $this->assertNull($object->hasAutoShrinkVertical());
+        self::assertInstanceOf(RichText::class, $object->setAutoShrinkVertical(null));
+        self::assertNull($object->hasAutoShrinkVertical());
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoShrinkVertical(true));
-        $this->assertTrue($object->hasAutoShrinkVertical());
+        self::assertInstanceOf(RichText::class, $object->setAutoShrinkVertical(true));
+        self::assertTrue($object->hasAutoShrinkVertical());
 
-        $this->assertInstanceOf(RichText::class, $object->setAutoShrinkVertical(false));
-        $this->assertFalse($object->hasAutoShrinkVertical());
+        self::assertInstanceOf(RichText::class, $object->setAutoShrinkVertical(false));
+        self::assertFalse($object->hasAutoShrinkVertical());
     }
 
     public function testGetSetHOverflow(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(RichText::class, $object->setHorizontalOverflow());
-        $this->assertEquals(RichText::OVERFLOW_OVERFLOW, $object->getHorizontalOverflow());
+        self::assertInstanceOf(RichText::class, $object->setHorizontalOverflow());
+        self::assertEquals(RichText::OVERFLOW_OVERFLOW, $object->getHorizontalOverflow());
 
-        $this->assertInstanceOf(RichText::class, $object->setHorizontalOverflow(RichText::OVERFLOW_CLIP));
-        $this->assertEquals(RichText::OVERFLOW_CLIP, $object->getHorizontalOverflow());
+        self::assertInstanceOf(RichText::class, $object->setHorizontalOverflow(RichText::OVERFLOW_CLIP));
+        self::assertEquals(RichText::OVERFLOW_CLIP, $object->getHorizontalOverflow());
     }
 
     public function testGetSetInset(): void
@@ -202,75 +201,75 @@ public function testGetSetInset(): void
         $object = new RichText();
 
         // Default
-        $this->assertInstanceOf(RichText::class, $object->setInsetBottom());
-        $this->assertEquals(4.8, $object->getInsetBottom());
-        $this->assertInstanceOf(RichText::class, $object->setInsetLeft());
-        $this->assertEquals(9.6, $object->getInsetLeft());
-        $this->assertInstanceOf(RichText::class, $object->setInsetRight());
-        $this->assertEquals(9.6, $object->getInsetRight());
-        $this->assertInstanceOf(RichText::class, $object->setInsetTop());
-        $this->assertEquals(4.8, $object->getInsetTop());
+        self::assertInstanceOf(RichText::class, $object->setInsetBottom());
+        self::assertEquals(4.8, $object->getInsetBottom());
+        self::assertInstanceOf(RichText::class, $object->setInsetLeft());
+        self::assertEquals(9.6, $object->getInsetLeft());
+        self::assertInstanceOf(RichText::class, $object->setInsetRight());
+        self::assertEquals(9.6, $object->getInsetRight());
+        self::assertInstanceOf(RichText::class, $object->setInsetTop());
+        self::assertEquals(4.8, $object->getInsetTop());
 
         // Value
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(RichText::class, $object->setInsetBottom($value));
-        $this->assertEquals($value, $object->getInsetBottom());
-        $this->assertInstanceOf(RichText::class, $object->setInsetLeft($value));
-        $this->assertEquals($value, $object->getInsetLeft());
-        $this->assertInstanceOf(RichText::class, $object->setInsetRight($value));
-        $this->assertEquals($value, $object->getInsetRight());
-        $this->assertInstanceOf(RichText::class, $object->setInsetTop($value));
-        $this->assertEquals($value, $object->getInsetTop());
+        self::assertInstanceOf(RichText::class, $object->setInsetBottom($value));
+        self::assertEquals($value, $object->getInsetBottom());
+        self::assertInstanceOf(RichText::class, $object->setInsetLeft($value));
+        self::assertEquals($value, $object->getInsetLeft());
+        self::assertInstanceOf(RichText::class, $object->setInsetRight($value));
+        self::assertEquals($value, $object->getInsetRight());
+        self::assertInstanceOf(RichText::class, $object->setInsetTop($value));
+        self::assertEquals($value, $object->getInsetTop());
     }
 
     public function testGetSetUpright(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(RichText::class, $object->setUpright());
-        $this->assertFalse($object->isUpright());
+        self::assertInstanceOf(RichText::class, $object->setUpright());
+        self::assertFalse($object->isUpright());
 
-        $this->assertInstanceOf(RichText::class, $object->setUpright(true));
-        $this->assertTrue($object->isUpright());
+        self::assertInstanceOf(RichText::class, $object->setUpright(true));
+        self::assertTrue($object->isUpright());
 
-        $this->assertInstanceOf(RichText::class, $object->setUpright(false));
-        $this->assertFalse($object->isUpright());
+        self::assertInstanceOf(RichText::class, $object->setUpright(false));
+        self::assertFalse($object->isUpright());
     }
 
     public function testGetSetVertical(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(RichText::class, $object->setVertical());
-        $this->assertFalse($object->isVertical());
+        self::assertInstanceOf(RichText::class, $object->setVertical());
+        self::assertFalse($object->isVertical());
 
-        $this->assertInstanceOf(RichText::class, $object->setVertical(true));
-        $this->assertTrue($object->isVertical());
+        self::assertInstanceOf(RichText::class, $object->setVertical(true));
+        self::assertTrue($object->isVertical());
 
-        $this->assertInstanceOf(RichText::class, $object->setVertical(false));
-        $this->assertFalse($object->isVertical());
+        self::assertInstanceOf(RichText::class, $object->setVertical(false));
+        self::assertFalse($object->isVertical());
     }
 
     public function testGetSetVOverflow(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(RichText::class, $object->setVerticalOverflow());
-        $this->assertEquals(RichText::OVERFLOW_OVERFLOW, $object->getVerticalOverflow());
+        self::assertInstanceOf(RichText::class, $object->setVerticalOverflow());
+        self::assertEquals(RichText::OVERFLOW_OVERFLOW, $object->getVerticalOverflow());
 
-        $this->assertInstanceOf(RichText::class, $object->setVerticalOverflow(RichText::OVERFLOW_CLIP));
-        $this->assertEquals(RichText::OVERFLOW_CLIP, $object->getVerticalOverflow());
+        self::assertInstanceOf(RichText::class, $object->setVerticalOverflow(RichText::OVERFLOW_CLIP));
+        self::assertEquals(RichText::OVERFLOW_CLIP, $object->getVerticalOverflow());
     }
 
     public function testGetSetWrap(): void
     {
         $object = new RichText();
 
-        $this->assertInstanceOf(RichText::class, $object->setWrap());
-        $this->assertEquals(RichText::WRAP_SQUARE, $object->getWrap());
+        self::assertInstanceOf(RichText::class, $object->setWrap());
+        self::assertEquals(RichText::WRAP_SQUARE, $object->getWrap());
 
-        $this->assertInstanceOf(RichText::class, $object->setWrap(RichText::WRAP_NONE));
-        $this->assertEquals(RichText::WRAP_NONE, $object->getWrap());
+        self::assertInstanceOf(RichText::class, $object->setWrap(RichText::WRAP_NONE));
+        self::assertEquals(RichText::WRAP_NONE, $object->getWrap());
     }
 
     public function testHashCode(): void
@@ -281,6 +280,6 @@ public function testHashCode(): void
         $hash .= RichText::WRAP_SQUARE . RichText::AUTOFIT_DEFAULT . RichText::OVERFLOW_OVERFLOW . RichText::OVERFLOW_OVERFLOW . '00104.89.69.64.8';
         $hash .= md5('00000' . $object->getFill()->getHashCode() . $object->getShadow()->getHashCode() . '' . get_parent_class($object));
         $hash .= get_class($object);
-        $this->assertEquals(md5($hash), $object->getHashCode());
+        self::assertEquals(md5($hash), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Table/CellTest.php b/tests/PhpPresentation/Tests/Shape/Table/CellTest.php
index 7f0ccc502a..c4e1ee8b6e 100644
--- a/tests/PhpPresentation/Tests/Shape/Table/CellTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Table/CellTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -41,30 +40,30 @@ class CellTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Cell();
-        $this->assertEquals(0, $object->getActiveParagraphIndex());
-        $this->assertCount(1, $object->getParagraphs());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Borders', $object->getBorders());
+        self::assertEquals(0, $object->getActiveParagraphIndex());
+        self::assertCount(1, $object->getParagraphs());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Borders', $object->getBorders());
     }
 
     public function testActiveParagraph(): void
     {
         $object = new Cell();
-        $this->assertEquals(0, $object->getActiveParagraphIndex());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->createParagraph());
-        $this->assertCount(2, $object->getParagraphs());
+        self::assertEquals(0, $object->getActiveParagraphIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->createParagraph());
+        self::assertCount(2, $object->getParagraphs());
         $value = mt_rand(0, 1);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->setActiveParagraph($value));
-        $this->assertEquals($value, $object->getActiveParagraphIndex());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->getActiveParagraph());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->getParagraph());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->setActiveParagraph($value));
+        self::assertEquals($value, $object->getActiveParagraphIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->getActiveParagraph());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->getParagraph());
         $value = mt_rand(0, 1);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->getParagraph($value));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->getParagraph($value));
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setParagraphs([]));
-        $this->assertCount(0, $object->getParagraphs());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->createParagraph());
-        $this->assertCount(1, $object->getParagraphs());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setParagraphs([]));
+        self::assertCount(0, $object->getParagraphs());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Paragraph', $object->createParagraph());
+        self::assertCount(1, $object->getParagraphs());
     }
 
     public function testActiveParagraphException(): void
@@ -93,28 +92,28 @@ public function testSetGetHashIndex(): void
         $object = new Cell();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testText(): void
     {
         $object = new Cell();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->addText());
-        $this->assertCount(1, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->addText(new TextElement()));
-        $this->assertCount(2, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->createText());
-        $this->assertCount(3, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->createText('ALPHA'));
-        $this->assertCount(4, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->createBreak());
-        $this->assertCount(5, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->createTextRun());
-        $this->assertCount(6, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->createTextRun('BETA'));
-        $this->assertCount(7, $object->getActiveParagraph()->getRichTextElements());
-        $this->assertEquals('ALPHA' . "\r\n" . 'BETA', $object->getPlainText());
-        $this->assertEquals('ALPHA' . "\r\n" . 'BETA', (string) $object);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->addText());
+        self::assertCount(1, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->addText(new TextElement()));
+        self::assertCount(2, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->createText());
+        self::assertCount(3, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\TextElement', $object->createText('ALPHA'));
+        self::assertCount(4, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\BreakElement', $object->createBreak());
+        self::assertCount(5, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->createTextRun());
+        self::assertCount(6, $object->getActiveParagraph()->getRichTextElements());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText\\Run', $object->createTextRun('BETA'));
+        self::assertCount(7, $object->getActiveParagraph()->getRichTextElements());
+        self::assertEquals('ALPHA' . "\r\n" . 'BETA', $object->getPlainText());
+        self::assertEquals('ALPHA' . "\r\n" . 'BETA', (string) $object);
     }
 
     public function testParagraphs(): void
@@ -127,60 +126,60 @@ public function testParagraphs(): void
             new Paragraph(),
         ];
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setParagraphs($array));
-        $this->assertCount(3, $object->getParagraphs());
-        $this->assertEquals(2, $object->getActiveParagraphIndex());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setParagraphs($array));
+        self::assertCount(3, $object->getParagraphs());
+        self::assertEquals(2, $object->getActiveParagraphIndex());
     }
 
     public function testGetSetBorders(): void
     {
         $object = new Cell();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setBorders(new Borders()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Borders', $object->getBorders());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setBorders(new Borders()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Borders', $object->getBorders());
     }
 
     public function testGetSetColspan(): void
     {
         $object = new Cell();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setColSpan());
-        $this->assertEquals(0, $object->getColSpan());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setColSpan());
+        self::assertEquals(0, $object->getColSpan());
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setColSpan($value));
-        $this->assertEquals($value, $object->getColSpan());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setColSpan($value));
+        self::assertEquals($value, $object->getColSpan());
     }
 
     public function testGetSetFill(): void
     {
         $object = new Cell();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setFill(new Fill()));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setFill(new Fill()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Fill', $object->getFill());
     }
 
     public function testGetSetRowspan(): void
     {
         $object = new Cell();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setRowSpan());
-        $this->assertEquals(0, $object->getRowSpan());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setRowSpan());
+        self::assertEquals(0, $object->getRowSpan());
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setRowSpan($value));
-        $this->assertEquals($value, $object->getRowSpan());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setRowSpan($value));
+        self::assertEquals($value, $object->getRowSpan());
     }
 
     public function testGetSetWidth(): void
     {
         $object = new Cell();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setWidth());
-        $this->assertEquals(0, $object->getWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setWidth());
+        self::assertEquals(0, $object->getWidth());
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setWidth($value));
-        $this->assertEquals($value, $object->getWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Cell', $object->setWidth($value));
+        self::assertEquals($value, $object->getWidth());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/Table/RowTest.php b/tests/PhpPresentation/Tests/Shape/Table/RowTest.php
index 2e8ed0595e..26597a5faf 100644
--- a/tests/PhpPresentation/Tests/Shape/Table/RowTest.php
+++ b/tests/PhpPresentation/Tests/Shape/Table/RowTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -39,20 +38,20 @@ class RowTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Row();
-        $this->assertCount(1, $object->getCells());
-        $this->assertInstanceOf(Fill::class, $object->getFill());
+        self::assertCount(1, $object->getCells());
+        self::assertInstanceOf(Fill::class, $object->getFill());
 
         $value = mt_rand(1, 100);
         $object = new Row($value);
-        $this->assertCount($value, $object->getCells());
-        $this->assertInstanceOf(Fill::class, $object->getFill());
+        self::assertCount($value, $object->getCells());
+        self::assertInstanceOf(Fill::class, $object->getFill());
     }
 
     public function testGetCell(): void
     {
         $object = new Row();
 
-        $this->assertInstanceOf(Cell::class, $object->getCell(0));
+        self::assertInstanceOf(Cell::class, $object->getCell(0));
     }
 
     public function testGetCellException(): void
@@ -68,7 +67,7 @@ public function testNextCell(): void
     {
         $object = new Row(2);
 
-        $this->assertInstanceOf(Cell::class, $object->nextCell());
+        self::assertInstanceOf(Cell::class, $object->nextCell());
     }
 
     public function testNextCellException(): void
@@ -89,26 +88,26 @@ public function testSetGetHashIndex(): void
         $object = new Row();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     public function testGetSetFill(): void
     {
         $object = new Row();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Row', $object->setFill(new Fill()));
-        $this->assertInstanceOf(Fill::class, $object->getFill());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Row', $object->setFill(new Fill()));
+        self::assertInstanceOf(Fill::class, $object->getFill());
     }
 
     public function testGetSetHeight(): void
     {
         $object = new Row();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Row', $object->setHeight());
-        $this->assertEquals(0, $object->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Row', $object->setHeight());
+        self::assertEquals(0, $object->getHeight());
 
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Row', $object->setHeight($value));
-        $this->assertEquals($value, $object->getHeight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Table\\Row', $object->setHeight($value));
+        self::assertEquals($value, $object->getHeight());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Shape/TableTest.php b/tests/PhpPresentation/Tests/Shape/TableTest.php
index 286b151e9c..524aa29a99 100644
--- a/tests/PhpPresentation/Tests/Shape/TableTest.php
+++ b/tests/PhpPresentation/Tests/Shape/TableTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,8 +34,8 @@ class TableTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Table();
-        $this->assertEmpty($object->getRows());
-        $this->assertFalse($object->isResizeProportional());
+        self::assertEmpty($object->getRows());
+        self::assertFalse($object->isResizeProportional());
     }
 
     public function testNumColums(): void
@@ -44,19 +43,19 @@ public function testNumColums(): void
         $value = mt_rand(1, 100);
         $object = new Table();
 
-        $this->assertEquals(1, $object->getNumColumns());
-        $this->assertInstanceOf(Table::class, $object->setNumColumns($value));
-        $this->assertEquals($value, $object->getNumColumns());
+        self::assertEquals(1, $object->getNumColumns());
+        self::assertInstanceOf(Table::class, $object->setNumColumns($value));
+        self::assertEquals($value, $object->getNumColumns());
     }
 
     public function testRows(): void
     {
         $object = new Table();
 
-        $this->assertInstanceOf(Row::class, $object->createRow());
-        $this->assertCount(1, $object->getRows());
+        self::assertInstanceOf(Row::class, $object->createRow());
+        self::assertCount(1, $object->getRows());
 
-        $this->assertInstanceOf(Row::class, $object->getRow(0));
+        self::assertInstanceOf(Row::class, $object->getRow(0));
     }
 
     public function testGetRowException(): void
@@ -71,9 +70,9 @@ public function testGetRowException(): void
     public function testHashCode(): void
     {
         $object = new Table();
-        $this->assertEquals(md5(get_class($object)), $object->getHashCode());
+        self::assertEquals(md5(get_class($object)), $object->getHashCode());
 
         $row = $object->createRow();
-        $this->assertEquals(md5($row->getHashCode() . get_class($object)), $object->getHashCode());
+        self::assertEquals(md5($row->getHashCode() . get_class($object)), $object->getHashCode());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/AbstractSlideTest.php b/tests/PhpPresentation/Tests/Slide/AbstractSlideTest.php
index 16fd597785..d8d67a56f3 100644
--- a/tests/PhpPresentation/Tests/Slide/AbstractSlideTest.php
+++ b/tests/PhpPresentation/Tests/Slide/AbstractSlideTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,17 +36,17 @@ public function testCollection(): void
         $stub = $this->getMockForAbstractClass('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide');
 
         $array = [];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide', $stub->setShapeCollection($array));
-        $this->assertIsArray($stub->getShapeCollection());
-        $this->assertCount(count($array), $stub->getShapeCollection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide', $stub->setShapeCollection($array));
+        self::assertIsArray($stub->getShapeCollection());
+        self::assertCount(count($array), $stub->getShapeCollection());
 
         $array = [
             new RichText(),
             new RichText(),
             new RichText(),
         ];
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide', $stub->setShapeCollection($array));
-        $this->assertIsArray($stub->getShapeCollection());
-        $this->assertCount(count($array), $stub->getShapeCollection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide', $stub->setShapeCollection($array));
+        self::assertIsArray($stub->getShapeCollection());
+        self::assertCount(count($array), $stub->getShapeCollection());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/AnimationTest.php b/tests/PhpPresentation/Tests/Slide/AnimationTest.php
index 84d48cee0a..6056202cc2 100644
--- a/tests/PhpPresentation/Tests/Slide/AnimationTest.php
+++ b/tests/PhpPresentation/Tests/Slide/AnimationTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -38,16 +37,16 @@ public function testShape(): void
 
         $object = new Animation();
 
-        $this->assertIsArray($object->getShapeCollection());
-        $this->assertCount(0, $object->getShapeCollection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Animation', $object->addShape($oStub));
-        $this->assertIsArray($object->getShapeCollection());
-        $this->assertCount(1, $object->getShapeCollection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Animation', $object->setShapeCollection());
-        $this->assertIsArray($object->getShapeCollection());
-        $this->assertCount(0, $object->getShapeCollection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Animation', $object->setShapeCollection([$oStub]));
-        $this->assertIsArray($object->getShapeCollection());
-        $this->assertCount(1, $object->getShapeCollection());
+        self::assertIsArray($object->getShapeCollection());
+        self::assertCount(0, $object->getShapeCollection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Animation', $object->addShape($oStub));
+        self::assertIsArray($object->getShapeCollection());
+        self::assertCount(1, $object->getShapeCollection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Animation', $object->setShapeCollection());
+        self::assertIsArray($object->getShapeCollection());
+        self::assertCount(0, $object->getShapeCollection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Animation', $object->setShapeCollection([$oStub]));
+        self::assertIsArray($object->getShapeCollection());
+        self::assertCount(1, $object->getShapeCollection());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/Background/ColorTest.php b/tests/PhpPresentation/Tests/Slide/Background/ColorTest.php
index 02946f7a86..a26e10d50b 100644
--- a/tests/PhpPresentation/Tests/Slide/Background/ColorTest.php
+++ b/tests/PhpPresentation/Tests/Slide/Background/ColorTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -33,10 +32,10 @@ public function testColor(): void
         $oStyleColor = new StyleColor();
         $oStyleColor->setRGB('123456');
 
-        $this->assertNull($object->getColor());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\Color', $object->setColor($oStyleColor));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\Color', $object->setColor());
-        $this->assertNull($object->getColor());
+        self::assertNull($object->getColor());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\Color', $object->setColor($oStyleColor));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\Color', $object->setColor());
+        self::assertNull($object->getColor());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/Background/ImageTest.php b/tests/PhpPresentation/Tests/Slide/Background/ImageTest.php
index be9251773b..a4efc0525c 100644
--- a/tests/PhpPresentation/Tests/Slide/Background/ImageTest.php
+++ b/tests/PhpPresentation/Tests/Slide/Background/ImageTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -33,22 +32,22 @@ public function testColor(): void
         $imagePath = PHPPRESENTATION_TESTS_BASE_DIR . DIRECTORY_SEPARATOR . 'resources' . DIRECTORY_SEPARATOR . 'images' . DIRECTORY_SEPARATOR . 'PhpPresentationLogo.png';
         $numSlide = (string) mt_rand(1, 100);
 
-        $this->assertNull($object->getPath());
-        $this->assertEmpty($object->getFilename());
-        $this->assertEmpty($object->getExtension());
-        $this->assertEquals('background_' . $numSlide . '.', $object->getIndexedFilename($numSlide));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\Image', $object->setPath($imagePath));
-        $this->assertEquals($imagePath, $object->getPath());
-        $this->assertEquals('PhpPresentationLogo.png', $object->getFilename());
-        $this->assertEquals('png', $object->getExtension());
-        $this->assertEquals('background_' . $numSlide . '.png', $object->getIndexedFilename($numSlide));
-
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\Image', $object->setPath('', false));
-        $this->assertEquals('', $object->getPath());
-        $this->assertEmpty($object->getFilename());
-        $this->assertEmpty($object->getExtension());
-        $this->assertEquals('background_' . $numSlide . '.', $object->getIndexedFilename($numSlide));
+        self::assertNull($object->getPath());
+        self::assertEmpty($object->getFilename());
+        self::assertEmpty($object->getExtension());
+        self::assertEquals('background_' . $numSlide . '.', $object->getIndexedFilename($numSlide));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\Image', $object->setPath($imagePath));
+        self::assertEquals($imagePath, $object->getPath());
+        self::assertEquals('PhpPresentationLogo.png', $object->getFilename());
+        self::assertEquals('png', $object->getExtension());
+        self::assertEquals('background_' . $numSlide . '.png', $object->getIndexedFilename($numSlide));
+
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\Image', $object->setPath('', false));
+        self::assertEquals('', $object->getPath());
+        self::assertEmpty($object->getFilename());
+        self::assertEmpty($object->getExtension());
+        self::assertEquals('background_' . $numSlide . '.', $object->getIndexedFilename($numSlide));
     }
 
     public function testPathException(): void
diff --git a/tests/PhpPresentation/Tests/Slide/Background/SchemeColorTest.php b/tests/PhpPresentation/Tests/Slide/Background/SchemeColorTest.php
index cdf5142ff1..c1cb4890cf 100644
--- a/tests/PhpPresentation/Tests/Slide/Background/SchemeColorTest.php
+++ b/tests/PhpPresentation/Tests/Slide/Background/SchemeColorTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -32,12 +31,12 @@ public function testBasic(): void
 
         $object = new SchemeColor();
 
-        $this->assertNull($object->getSchemeColor());
+        self::assertNull($object->getSchemeColor());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\SchemeColor', $object->setSchemeColor($oStyle));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\SchemeColor', $object->getSchemeColor());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\SchemeColor', $object->setSchemeColor($oStyle));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\SchemeColor', $object->getSchemeColor());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\SchemeColor', $object->setSchemeColor());
-        $this->assertNull($object->getSchemeColor());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Background\\SchemeColor', $object->setSchemeColor());
+        self::assertNull($object->getSchemeColor());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/IteratorTest.php b/tests/PhpPresentation/Tests/Slide/IteratorTest.php
index 480e874d4d..5ab9666961 100644
--- a/tests/PhpPresentation/Tests/Slide/IteratorTest.php
+++ b/tests/PhpPresentation/Tests/Slide/IteratorTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -39,15 +38,15 @@ public function testMethod(): void
 
         $object = new Iterator($oPhpPresentation);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide', $object->current());
-        $this->assertEquals(0, $object->key());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide', $object->current());
+        self::assertEquals(0, $object->key());
         $object->next();
-        $this->assertEquals(1, $object->key());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide', $object->current());
-        $this->assertTrue($object->valid());
+        self::assertEquals(1, $object->key());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide', $object->current());
+        self::assertTrue($object->valid());
         $object->next();
-        $this->assertFalse($object->valid());
+        self::assertFalse($object->valid());
         $object->rewind();
-        $this->assertEquals(0, $object->key());
+        self::assertEquals(0, $object->key());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/NoteTest.php b/tests/PhpPresentation/Tests/Slide/NoteTest.php
index 7b40555fb8..5cf4ce0209 100644
--- a/tests/PhpPresentation/Tests/Slide/NoteTest.php
+++ b/tests/PhpPresentation/Tests/Slide/NoteTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -35,48 +34,48 @@ class NoteTest extends TestCase
     public function testParent(): void
     {
         $object = new Note();
-        $this->assertNull($object->getParent());
+        self::assertNull($object->getParent());
 
         $oPhpPresentation = new PhpPresentation();
         $oSlide = $oPhpPresentation->createSlide();
         $oSlide->setNote($object);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide', $object->getParent());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide', $object->getParent());
     }
 
     public function testExtent(): void
     {
         $object = new Note();
-        $this->assertNotNull($object->getExtentX());
+        self::assertNotNull($object->getExtentX());
 
         $object = new Note();
-        $this->assertNotNull($object->getExtentY());
+        self::assertNotNull($object->getExtentY());
     }
 
     public function testHashCode(): void
     {
         $object = new Note();
-        $this->assertIsString($object->getHashCode());
+        self::assertIsString($object->getHashCode());
     }
 
     public function testOffset(): void
     {
         $object = new Note();
-        $this->assertNotNull($object->getOffsetX());
+        self::assertNotNull($object->getOffsetX());
 
         $object = new Note();
-        $this->assertNotNull($object->getOffsetY());
+        self::assertNotNull($object->getOffsetY());
     }
 
     public function testShape(): void
     {
         $object = new Note();
-        $this->assertEquals(0, $object->getShapeCollection()->count());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText', $object->createRichTextShape());
-        $this->assertEquals(1, $object->getShapeCollection()->count());
+        self::assertEquals(0, $object->getShapeCollection()->count());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText', $object->createRichTextShape());
+        self::assertEquals(1, $object->getShapeCollection()->count());
 
         $oRichText = new RichText();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText', $object->addShape($oRichText));
-        $this->assertEquals(2, $object->getShapeCollection()->count());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\RichText', $object->addShape($oRichText));
+        self::assertEquals(2, $object->getShapeCollection()->count());
     }
 
     /**
@@ -86,8 +85,8 @@ public function testSetGetHashIndex(): void
     {
         $object = new Note();
         $value = mt_rand(1, 100);
-        $this->assertNull($object->getHashIndex());
+        self::assertNull($object->getHashIndex());
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/SlideLayoutTest.php b/tests/PhpPresentation/Tests/Slide/SlideLayoutTest.php
index 2fc7f7df00..b3d23a42da 100644
--- a/tests/PhpPresentation/Tests/Slide/SlideLayoutTest.php
+++ b/tests/PhpPresentation/Tests/Slide/SlideLayoutTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,9 +36,9 @@ public function testBase(): void
         $mockSlideMaster = $this->getMockForAbstractClass(SlideMaster::class);
 
         $object = new SlideLayout($mockSlideMaster);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide', $object);
-        $this->assertInstanceOf('\\ArrayObject', $object->getShapeCollection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->colorMap);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide', $object);
+        self::assertInstanceOf('\\ArrayObject', $object->getShapeCollection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->colorMap);
     }
 
     public function testLayoutName(): void
@@ -48,13 +47,13 @@ public function testLayoutName(): void
         $mockSlideMaster = $this->getMockForAbstractClass(SlideMaster::class);
 
         // Expected
-        $expectedLayoutName = 'Title' . rand(1, 100);
+        $expectedLayoutName = 'Title' . mt_rand(1, 100);
 
         $object = new SlideLayout($mockSlideMaster);
 
-        $this->assertNull($object->getLayoutName());
-        $this->assertInstanceOf(SlideLayout::class, $object->setLayoutName($expectedLayoutName));
-        $this->assertEquals($expectedLayoutName, $object->getLayoutName());
+        self::assertNull($object->getLayoutName());
+        self::assertInstanceOf(SlideLayout::class, $object->setLayoutName($expectedLayoutName));
+        self::assertEquals($expectedLayoutName, $object->getLayoutName());
     }
 
     public function testSlideMaster(): void
@@ -64,6 +63,6 @@ public function testSlideMaster(): void
 
         $object = new SlideLayout($mockSlideMaster);
 
-        $this->assertInstanceOf(SlideMaster::class, $object->getSlideMaster());
+        self::assertInstanceOf(SlideMaster::class, $object->getSlideMaster());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/SlideMasterTest.php b/tests/PhpPresentation/Tests/Slide/SlideMasterTest.php
index 4bda4aa516..e910ae79ac 100644
--- a/tests/PhpPresentation/Tests/Slide/SlideMasterTest.php
+++ b/tests/PhpPresentation/Tests/Slide/SlideMasterTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,15 +36,15 @@ class SlideMasterTest extends TestCase
     public function testBase(): void
     {
         $object = new SlideMaster();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide', $object);
-        $this->assertNull($object->getParent());
-        $this->assertInstanceOf('\\ArrayObject', $object->getShapeCollection());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->colorMap);
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\AbstractSlide', $object);
+        self::assertNull($object->getParent());
+        self::assertInstanceOf('\\ArrayObject', $object->getShapeCollection());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->colorMap);
         /** @var Color $background */
         $background = $object->getBackground();
-        $this->assertInstanceOf(Color::class, $background);
-        $this->assertEquals('FFFFFF', $background->getColor()->getRGB());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->getTextStyles());
+        self::assertInstanceOf(Color::class, $background);
+        self::assertEquals('FFFFFF', $background->getColor()->getRGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->getTextStyles());
     }
 
     public function testLayout(): void
@@ -56,10 +55,10 @@ public function testLayout(): void
         /** @var SlideLayout $mockSlideLayout */
         $mockSlideLayout = $this->getMockForAbstractClass(SlideLayout::class, [$object]);
 
-        $this->assertEmpty($object->getAllSlideLayouts());
-        $this->assertInstanceOf(SlideLayout::class, $object->createSlideLayout());
-        $this->assertInstanceOf(SlideLayout::class, $object->addSlideLayout($mockSlideLayout));
-        $this->assertCount(2, $object->getAllSlideLayouts());
+        self::assertEmpty($object->getAllSlideLayouts());
+        self::assertInstanceOf(SlideLayout::class, $object->createSlideLayout());
+        self::assertInstanceOf(SlideLayout::class, $object->addSlideLayout($mockSlideLayout));
+        self::assertCount(2, $object->getAllSlideLayouts());
     }
 
     public function testSchemeColors(): void
@@ -76,14 +75,14 @@ public function testSchemeColors(): void
 
         $object = new SlideMaster();
 
-        $this->assertIsArray($object->getAllSchemeColors());
-        $this->assertCount(12, $object->getAllSchemeColors());
+        self::assertIsArray($object->getAllSchemeColors());
+        self::assertCount(12, $object->getAllSchemeColors());
         // Add idem value
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\SlideMaster', $object->addSchemeColor($mockSchemeColorAccent1));
-        $this->assertCount(12, $object->getAllSchemeColors());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\SlideMaster', $object->addSchemeColor($mockSchemeColorAccent1));
+        self::assertCount(12, $object->getAllSchemeColors());
         // Add new value
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\SlideMaster', $object->addSchemeColor($mockSchemeColorNew));
-        $this->assertCount(13, $object->getAllSchemeColors());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\SlideMaster', $object->addSchemeColor($mockSchemeColorNew));
+        self::assertCount(13, $object->getAllSchemeColors());
     }
 
     public function testTextStyles(): void
@@ -94,8 +93,8 @@ public function testTextStyles(): void
 
         $object = new SlideMaster();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->getTextStyles());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\SlideMaster', $object->setTextStyles($mockTextStyle));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->getTextStyles());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->getTextStyles());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\SlideMaster', $object->setTextStyles($mockTextStyle));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->getTextStyles());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Slide/TransitionTest.php b/tests/PhpPresentation/Tests/Slide/TransitionTest.php
index 5afda6050a..836cc49372 100644
--- a/tests/PhpPresentation/Tests/Slide/TransitionTest.php
+++ b/tests/PhpPresentation/Tests/Slide/TransitionTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -33,52 +32,52 @@ class TransitionTest extends TestCase
     public function testSpeed(): void
     {
         $object = new Transition();
-        $this->assertNull($object->getSpeed());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setSpeed());
-        $this->assertEquals(Transition::SPEED_MEDIUM, $object->getSpeed());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setSpeed(Transition::SPEED_FAST));
-        $this->assertEquals(Transition::SPEED_FAST, $object->getSpeed());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setSpeed('notagoodvalue'));
-        $this->assertNull($object->getSpeed());
+        self::assertNull($object->getSpeed());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setSpeed());
+        self::assertEquals(Transition::SPEED_MEDIUM, $object->getSpeed());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setSpeed(Transition::SPEED_FAST));
+        self::assertEquals(Transition::SPEED_FAST, $object->getSpeed());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setSpeed('notagoodvalue'));
+        self::assertNull($object->getSpeed());
     }
 
     public function testManualTrigger(): void
     {
         $object = new Transition();
-        $this->assertFalse($object->hasManualTrigger());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setManualTrigger());
-        $this->assertFalse($object->hasManualTrigger());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setManualTrigger(true));
-        $this->assertTrue($object->hasManualTrigger());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setManualTrigger(false));
-        $this->assertFalse($object->hasManualTrigger());
+        self::assertFalse($object->hasManualTrigger());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setManualTrigger());
+        self::assertFalse($object->hasManualTrigger());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setManualTrigger(true));
+        self::assertTrue($object->hasManualTrigger());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setManualTrigger(false));
+        self::assertFalse($object->hasManualTrigger());
     }
 
     public function testTimeTrigger(): void
     {
         $object = new Transition();
-        $this->assertFalse($object->hasTimeTrigger());
-        $this->assertNull($object->getAdvanceTimeTrigger());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTimeTrigger());
-        $this->assertFalse($object->hasTimeTrigger());
-        $this->assertNull($object->getAdvanceTimeTrigger());
+        self::assertFalse($object->hasTimeTrigger());
+        self::assertNull($object->getAdvanceTimeTrigger());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTimeTrigger());
+        self::assertFalse($object->hasTimeTrigger());
+        self::assertNull($object->getAdvanceTimeTrigger());
         $value = mt_rand(1, 1000);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTimeTrigger(true, $value));
-        $this->assertTrue($object->hasTimeTrigger());
-        $this->assertEquals($value, $object->getAdvanceTimeTrigger());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTimeTrigger(true, $value));
+        self::assertTrue($object->hasTimeTrigger());
+        self::assertEquals($value, $object->getAdvanceTimeTrigger());
         $value = mt_rand(1, 1000);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTimeTrigger(false, $value));
-        $this->assertFalse($object->hasTimeTrigger());
-        $this->assertNull($object->getAdvanceTimeTrigger());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTimeTrigger(false, $value));
+        self::assertFalse($object->hasTimeTrigger());
+        self::assertNull($object->getAdvanceTimeTrigger());
     }
 
     public function testTransitionType(): void
     {
         $object = new Transition();
-        $this->assertNull($object->getTransitionType());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTransitionType());
-        $this->assertNull($object->getTransitionType());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTransitionType(Transition::TRANSITION_RANDOM));
-        $this->assertEquals(Transition::TRANSITION_RANDOM, $object->getTransitionType());
+        self::assertNull($object->getTransitionType());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTransitionType());
+        self::assertNull($object->getTransitionType());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Slide\\Transition', $object->setTransitionType(Transition::TRANSITION_RANDOM));
+        self::assertEquals(Transition::TRANSITION_RANDOM, $object->getTransitionType());
     }
 }
diff --git a/tests/PhpPresentation/Tests/SlideTest.php b/tests/PhpPresentation/Tests/SlideTest.php
index eea3f731d9..99fff513c1 100644
--- a/tests/PhpPresentation/Tests/SlideTest.php
+++ b/tests/PhpPresentation/Tests/SlideTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,40 +36,40 @@ class SlideTest extends TestCase
     public function testExtents(): void
     {
         $object = new Slide();
-        $this->assertNotNull($object->getExtentX());
+        self::assertNotNull($object->getExtentX());
 
         $object = new Slide();
-        $this->assertNotNull($object->getExtentY());
+        self::assertNotNull($object->getExtentY());
     }
 
     public function testOffset(): void
     {
         $object = new Slide();
-        $this->assertNotNull($object->getOffsetX());
+        self::assertNotNull($object->getOffsetX());
 
         $object = new Slide();
-        $this->assertNotNull($object->getOffsetY());
+        self::assertNotNull($object->getOffsetY());
     }
 
     public function testParent(): void
     {
         $object = new Slide();
-        $this->assertNull($object->getParent());
+        self::assertNull($object->getParent());
 
         $oPhpPresentation = new PhpPresentation();
         $object = new Slide($oPhpPresentation);
-        $this->assertInstanceOf(PhpPresentation::class, $object->getParent());
+        self::assertInstanceOf(PhpPresentation::class, $object->getParent());
     }
 
     public function testSlideMasterId(): void
     {
         $value = mt_rand(1, 100);
         $object = new Slide();
-        $this->assertEquals(1, $object->getSlideMasterId());
-        $this->assertInstanceOf(Slide::class, $object->setSlideMasterId());
-        $this->assertEquals(1, $object->getSlideMasterId());
-        $this->assertInstanceOf(Slide::class, $object->setSlideMasterId($value));
-        $this->assertEquals($value, $object->getSlideMasterId());
+        self::assertEquals(1, $object->getSlideMasterId());
+        self::assertInstanceOf(Slide::class, $object->setSlideMasterId());
+        self::assertEquals(1, $object->getSlideMasterId());
+        self::assertInstanceOf(Slide::class, $object->setSlideMasterId($value));
+        self::assertEquals($value, $object->getSlideMasterId());
     }
 
     public function testAnimations(): void
@@ -79,17 +78,17 @@ public function testAnimations(): void
         $oStub = $this->getMockForAbstractClass(Animation::class);
 
         $object = new Slide();
-        $this->assertIsArray($object->getAnimations());
-        $this->assertCount(0, $object->getAnimations());
-        $this->assertInstanceOf(Slide::class, $object->addAnimation($oStub));
-        $this->assertIsArray($object->getAnimations());
-        $this->assertCount(1, $object->getAnimations());
-        $this->assertInstanceOf(Slide::class, $object->setAnimations());
-        $this->assertIsArray($object->getAnimations());
-        $this->assertCount(0, $object->getAnimations());
-        $this->assertInstanceOf(Slide::class, $object->setAnimations([$oStub]));
-        $this->assertIsArray($object->getAnimations());
-        $this->assertCount(1, $object->getAnimations());
+        self::assertIsArray($object->getAnimations());
+        self::assertCount(0, $object->getAnimations());
+        self::assertInstanceOf(Slide::class, $object->addAnimation($oStub));
+        self::assertIsArray($object->getAnimations());
+        self::assertCount(1, $object->getAnimations());
+        self::assertInstanceOf(Slide::class, $object->setAnimations());
+        self::assertIsArray($object->getAnimations());
+        self::assertCount(0, $object->getAnimations());
+        self::assertInstanceOf(Slide::class, $object->setAnimations([$oStub]));
+        self::assertIsArray($object->getAnimations());
+        self::assertCount(1, $object->getAnimations());
     }
 
     public function testBackground(): void
@@ -98,49 +97,49 @@ public function testBackground(): void
         $oStub = $this->getMockForAbstractClass(AbstractBackground::class);
 
         $object = new Slide();
-        $this->assertNull($object->getBackground());
-        $this->assertInstanceOf(Slide::class, $object->setBackground($oStub));
-        $this->assertInstanceOf(AbstractBackground::class, $object->getBackground());
-        $this->assertInstanceOf(Slide::class, $object->setBackground());
-        $this->assertNull($object->getBackground());
+        self::assertNull($object->getBackground());
+        self::assertInstanceOf(Slide::class, $object->setBackground($oStub));
+        self::assertInstanceOf(AbstractBackground::class, $object->getBackground());
+        self::assertInstanceOf(Slide::class, $object->setBackground());
+        self::assertNull($object->getBackground());
     }
 
     public function testGroup(): void
     {
         $object = new Slide();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->createGroup());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Group', $object->createGroup());
     }
 
     public function testName(): void
     {
         $object = new Slide();
-        $this->assertNull($object->getName());
-        $this->assertInstanceOf(Slide::class, $object->setName('AAAA'));
-        $this->assertEquals('AAAA', $object->getName());
-        $this->assertInstanceOf(Slide::class, $object->setName());
-        $this->assertNull($object->getName());
+        self::assertNull($object->getName());
+        self::assertInstanceOf(Slide::class, $object->setName('AAAA'));
+        self::assertEquals('AAAA', $object->getName());
+        self::assertInstanceOf(Slide::class, $object->setName());
+        self::assertNull($object->getName());
     }
 
     public function testTransition(): void
     {
         $object = new Slide();
         $oTransition = new Transition();
-        $this->assertNull($object->getTransition());
-        $this->assertInstanceOf(Slide::class, $object->setTransition());
-        $this->assertNull($object->getTransition());
-        $this->assertInstanceOf(Slide::class, $object->setTransition($oTransition));
-        $this->assertInstanceOf(Transition::class, $object->getTransition());
-        $this->assertInstanceOf(Slide::class, $object->setTransition(null));
-        $this->assertNull($object->getTransition());
+        self::assertNull($object->getTransition());
+        self::assertInstanceOf(Slide::class, $object->setTransition());
+        self::assertNull($object->getTransition());
+        self::assertInstanceOf(Slide::class, $object->setTransition($oTransition));
+        self::assertInstanceOf(Transition::class, $object->getTransition());
+        self::assertInstanceOf(Slide::class, $object->setTransition(null));
+        self::assertNull($object->getTransition());
     }
 
     public function testVisible(): void
     {
         $object = new Slide();
-        $this->assertTrue($object->isVisible());
-        $this->assertInstanceOf(Slide::class, $object->setIsVisible(false));
-        $this->assertFalse($object->isVisible());
-        $this->assertInstanceOf(Slide::class, $object->setIsVisible());
-        $this->assertTrue($object->isVisible());
+        self::assertTrue($object->isVisible());
+        self::assertInstanceOf(Slide::class, $object->setIsVisible(false));
+        self::assertFalse($object->isVisible());
+        self::assertInstanceOf(Slide::class, $object->setIsVisible());
+        self::assertTrue($object->isVisible());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/AlignmentTest.php b/tests/PhpPresentation/Tests/Style/AlignmentTest.php
index 510811fb48..ca16511747 100644
--- a/tests/PhpPresentation/Tests/Style/AlignmentTest.php
+++ b/tests/PhpPresentation/Tests/Style/AlignmentTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,15 +36,15 @@ class AlignmentTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Alignment();
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $object->getHorizontal());
-        $this->assertEquals(Alignment::VERTICAL_BASE, $object->getVertical());
-        $this->assertEquals(Alignment::TEXT_DIRECTION_HORIZONTAL, $object->getTextDirection());
-        $this->assertEquals(0, $object->getLevel());
-        $this->assertEquals(0, $object->getIndent());
-        $this->assertEquals(0, $object->getMarginLeft());
-        $this->assertEquals(0, $object->getMarginRight());
-        $this->assertEquals(0, $object->getMarginTop());
-        $this->assertEquals(0, $object->getMarginBottom());
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $object->getHorizontal());
+        self::assertEquals(Alignment::VERTICAL_BASE, $object->getVertical());
+        self::assertEquals(Alignment::TEXT_DIRECTION_HORIZONTAL, $object->getTextDirection());
+        self::assertEquals(0, $object->getLevel());
+        self::assertEquals(0, $object->getIndent());
+        self::assertEquals(0, $object->getMarginLeft());
+        self::assertEquals(0, $object->getMarginRight());
+        self::assertEquals(0, $object->getMarginTop());
+        self::assertEquals(0, $object->getMarginBottom());
     }
 
     /**
@@ -54,10 +53,10 @@ public function testConstruct(): void
     public function testSetGetHorizontal(): void
     {
         $object = new Alignment();
-        $this->assertInstanceOf(Alignment::class, $object->setHorizontal(''));
-        $this->assertEquals(Alignment::HORIZONTAL_LEFT, $object->getHorizontal());
-        $this->assertInstanceOf(Alignment::class, $object->setHorizontal(Alignment::HORIZONTAL_GENERAL));
-        $this->assertEquals(Alignment::HORIZONTAL_GENERAL, $object->getHorizontal());
+        self::assertInstanceOf(Alignment::class, $object->setHorizontal(''));
+        self::assertEquals(Alignment::HORIZONTAL_LEFT, $object->getHorizontal());
+        self::assertInstanceOf(Alignment::class, $object->setHorizontal(Alignment::HORIZONTAL_GENERAL));
+        self::assertEquals(Alignment::HORIZONTAL_GENERAL, $object->getHorizontal());
     }
 
     /**
@@ -66,12 +65,12 @@ public function testSetGetHorizontal(): void
     public function testTextDirection(): void
     {
         $object = new Alignment();
-        $this->assertInstanceOf(Alignment::class, $object->setTextDirection(''));
-        $this->assertEquals(Alignment::TEXT_DIRECTION_HORIZONTAL, $object->getTextDirection());
-        $this->assertInstanceOf(Alignment::class, $object->setTextDirection(Alignment::TEXT_DIRECTION_VERTICAL_90));
-        $this->assertEquals(Alignment::TEXT_DIRECTION_VERTICAL_90, $object->getTextDirection());
-        $this->assertInstanceOf(Alignment::class, $object->setTextDirection());
-        $this->assertEquals(Alignment::TEXT_DIRECTION_HORIZONTAL, $object->getTextDirection());
+        self::assertInstanceOf(Alignment::class, $object->setTextDirection(''));
+        self::assertEquals(Alignment::TEXT_DIRECTION_HORIZONTAL, $object->getTextDirection());
+        self::assertInstanceOf(Alignment::class, $object->setTextDirection(Alignment::TEXT_DIRECTION_VERTICAL_90));
+        self::assertEquals(Alignment::TEXT_DIRECTION_VERTICAL_90, $object->getTextDirection());
+        self::assertInstanceOf(Alignment::class, $object->setTextDirection());
+        self::assertEquals(Alignment::TEXT_DIRECTION_HORIZONTAL, $object->getTextDirection());
     }
 
     /**
@@ -80,10 +79,10 @@ public function testTextDirection(): void
     public function testSetGetVertical(): void
     {
         $object = new Alignment();
-        $this->assertInstanceOf(Alignment::class, $object->setVertical(''));
-        $this->assertEquals(Alignment::VERTICAL_BASE, $object->getVertical());
-        $this->assertInstanceOf(Alignment::class, $object->setVertical(Alignment::VERTICAL_AUTO));
-        $this->assertEquals(Alignment::VERTICAL_AUTO, $object->getVertical());
+        self::assertInstanceOf(Alignment::class, $object->setVertical(''));
+        self::assertEquals(Alignment::VERTICAL_BASE, $object->getVertical());
+        self::assertInstanceOf(Alignment::class, $object->setVertical(Alignment::VERTICAL_AUTO));
+        self::assertEquals(Alignment::VERTICAL_AUTO, $object->getVertical());
     }
 
     /**
@@ -105,8 +104,8 @@ public function testSetGetLevel(): void
     {
         $object = new Alignment();
         $value = mt_rand(1, 8);
-        $this->assertInstanceOf(Alignment::class, $object->setLevel($value));
-        $this->assertEquals($value, $object->getLevel());
+        self::assertInstanceOf(Alignment::class, $object->setLevel($value));
+        self::assertEquals($value, $object->getLevel());
     }
 
     /**
@@ -118,19 +117,19 @@ public function testSetGetIndent(): void
         // != Alignment::HORIZONTAL_GENERAL
         $object->setHorizontal(Alignment::HORIZONTAL_CENTER);
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Alignment::class, $object->setIndent($value));
-        $this->assertEquals(0, $object->getIndent());
+        self::assertInstanceOf(Alignment::class, $object->setIndent($value));
+        self::assertEquals(0, $object->getIndent());
         $value = mt_rand(-100, 0);
-        $this->assertInstanceOf(Alignment::class, $object->setIndent($value));
-        $this->assertEquals($value, $object->getIndent());
+        self::assertInstanceOf(Alignment::class, $object->setIndent($value));
+        self::assertEquals($value, $object->getIndent());
 
         $object->setHorizontal(Alignment::HORIZONTAL_GENERAL);
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Alignment::class, $object->setIndent($value));
-        $this->assertEquals($value, $object->getIndent());
+        self::assertInstanceOf(Alignment::class, $object->setIndent($value));
+        self::assertEquals($value, $object->getIndent());
         $value = mt_rand(-100, 0);
-        $this->assertInstanceOf(Alignment::class, $object->setIndent($value));
-        $this->assertEquals($value, $object->getIndent());
+        self::assertInstanceOf(Alignment::class, $object->setIndent($value));
+        self::assertEquals($value, $object->getIndent());
     }
 
     /**
@@ -140,10 +139,10 @@ public function testSetGetMarginBottom(): void
     {
         $object = new Alignment();
         $value = mt_rand(0, 100);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginBottom($value));
-        $this->assertEquals($value, $object->getMarginBottom());
-        $this->assertInstanceOf(Alignment::class, $object->setMarginBottom());
-        $this->assertEquals(0, $object->getMarginBottom());
+        self::assertInstanceOf(Alignment::class, $object->setMarginBottom($value));
+        self::assertEquals($value, $object->getMarginBottom());
+        self::assertInstanceOf(Alignment::class, $object->setMarginBottom());
+        self::assertEquals(0, $object->getMarginBottom());
     }
 
     /**
@@ -155,19 +154,19 @@ public function testSetGetMarginLeft(): void
         // != Alignment::HORIZONTAL_GENERAL
         $object->setHorizontal(Alignment::HORIZONTAL_CENTER);
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginLeft($value));
-        $this->assertEquals(0, $object->getMarginLeft());
+        self::assertInstanceOf(Alignment::class, $object->setMarginLeft($value));
+        self::assertEquals(0, $object->getMarginLeft());
         $value = mt_rand(-100, 0);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginLeft($value));
-        $this->assertEquals($value, $object->getMarginLeft());
+        self::assertInstanceOf(Alignment::class, $object->setMarginLeft($value));
+        self::assertEquals($value, $object->getMarginLeft());
 
         $object->setHorizontal(Alignment::HORIZONTAL_GENERAL);
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginLeft($value));
-        $this->assertEquals($value, $object->getMarginLeft());
+        self::assertInstanceOf(Alignment::class, $object->setMarginLeft($value));
+        self::assertEquals($value, $object->getMarginLeft());
         $value = mt_rand(-100, 0);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginLeft($value));
-        $this->assertEquals($value, $object->getMarginLeft());
+        self::assertInstanceOf(Alignment::class, $object->setMarginLeft($value));
+        self::assertEquals($value, $object->getMarginLeft());
     }
 
     /**
@@ -179,19 +178,19 @@ public function testSetGetMarginRight(): void
         // != Alignment::HORIZONTAL_GENERAL
         $object->setHorizontal(Alignment::HORIZONTAL_CENTER);
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginRight($value));
-        $this->assertEquals(0, $object->getMarginRight());
+        self::assertInstanceOf(Alignment::class, $object->setMarginRight($value));
+        self::assertEquals(0, $object->getMarginRight());
         $value = mt_rand(-100, 0);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginRight($value));
-        $this->assertEquals($value, $object->getMarginRight());
+        self::assertInstanceOf(Alignment::class, $object->setMarginRight($value));
+        self::assertEquals($value, $object->getMarginRight());
 
         $object->setHorizontal(Alignment::HORIZONTAL_GENERAL);
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginRight($value));
-        $this->assertEquals($value, $object->getMarginRight());
+        self::assertInstanceOf(Alignment::class, $object->setMarginRight($value));
+        self::assertEquals($value, $object->getMarginRight());
         $value = mt_rand(-100, 0);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginRight($value));
-        $this->assertEquals($value, $object->getMarginRight());
+        self::assertInstanceOf(Alignment::class, $object->setMarginRight($value));
+        self::assertEquals($value, $object->getMarginRight());
     }
 
     /**
@@ -201,22 +200,22 @@ public function testSetGetMarginTop(): void
     {
         $object = new Alignment();
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Alignment::class, $object->setMarginTop($value));
-        $this->assertEquals($value, $object->getMarginTop());
-        $this->assertInstanceOf(Alignment::class, $object->setMarginTop());
-        $this->assertEquals(0, $object->getMarginTop());
+        self::assertInstanceOf(Alignment::class, $object->setMarginTop($value));
+        self::assertEquals($value, $object->getMarginTop());
+        self::assertInstanceOf(Alignment::class, $object->setMarginTop());
+        self::assertEquals(0, $object->getMarginTop());
     }
 
     public function testRTL(): void
     {
         $object = new Alignment();
-        $this->assertFalse($object->isRTL());
-        $this->assertInstanceOf(Alignment::class, $object->setIsRTL(true));
-        $this->assertTrue($object->isRTL());
-        $this->assertInstanceOf(Alignment::class, $object->setIsRTL(false));
-        $this->assertFalse($object->isRTL());
-        $this->assertInstanceOf(Alignment::class, $object->setIsRTL());
-        $this->assertFalse($object->isRTL());
+        self::assertFalse($object->isRTL());
+        self::assertInstanceOf(Alignment::class, $object->setIsRTL(true));
+        self::assertTrue($object->isRTL());
+        self::assertInstanceOf(Alignment::class, $object->setIsRTL(false));
+        self::assertFalse($object->isRTL());
+        self::assertInstanceOf(Alignment::class, $object->setIsRTL());
+        self::assertFalse($object->isRTL());
     }
 
     /**
@@ -224,10 +223,10 @@ public function testRTL(): void
      */
     public function testSetGetHashIndex(): void
     {
-        $value = rand(1, 100);
+        $value = mt_rand(1, 100);
 
         $object = new Alignment();
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/BorderTest.php b/tests/PhpPresentation/Tests/Style/BorderTest.php
index 6084fa10c7..80b4d3498c 100644
--- a/tests/PhpPresentation/Tests/Style/BorderTest.php
+++ b/tests/PhpPresentation/Tests/Style/BorderTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,11 +36,11 @@ class BorderTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Border();
-        $this->assertEquals(1, $object->getLineWidth());
-        $this->assertEquals(Border::LINE_SINGLE, $object->getLineStyle());
-        $this->assertEquals(Border::DASH_SOLID, $object->getDashStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
-        $this->assertEquals('FF000000', $object->getColor()->getARGB());
+        self::assertEquals(1, $object->getLineWidth());
+        self::assertEquals(Border::LINE_SINGLE, $object->getLineStyle());
+        self::assertEquals(Border::DASH_SOLID, $object->getDashStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
+        self::assertEquals('FF000000', $object->getColor()->getARGB());
     }
 
     /**
@@ -50,11 +49,11 @@ public function testConstruct(): void
     public function testSetGetColor(): void
     {
         $object = new Border();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setColor());
-        $this->assertNull($object->getColor());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setColor(new Color(COLOR::COLOR_BLUE)));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
-        $this->assertEquals('FF0000FF', $object->getColor()->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setColor());
+        self::assertNull($object->getColor());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setColor(new Color(COLOR::COLOR_BLUE)));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
+        self::assertEquals('FF0000FF', $object->getColor()->getARGB());
     }
 
     /**
@@ -63,12 +62,12 @@ public function testSetGetColor(): void
     public function testSetGetDashStyle(): void
     {
         $object = new Border();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setDashStyle());
-        $this->assertEquals(Border::DASH_SOLID, $object->getDashStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setDashStyle(''));
-        $this->assertEquals(Border::DASH_SOLID, $object->getDashStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setDashStyle(BORDER::DASH_DASH));
-        $this->assertEquals(Border::DASH_DASH, $object->getDashStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setDashStyle());
+        self::assertEquals(Border::DASH_SOLID, $object->getDashStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setDashStyle(''));
+        self::assertEquals(Border::DASH_SOLID, $object->getDashStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setDashStyle(BORDER::DASH_DASH));
+        self::assertEquals(Border::DASH_DASH, $object->getDashStyle());
     }
 
     /**
@@ -79,7 +78,7 @@ public function testSetGetHashIndex(): void
         $object = new Border();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     /**
@@ -88,12 +87,12 @@ public function testSetGetHashIndex(): void
     public function testSetGetLineStyle(): void
     {
         $object = new Border();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineStyle());
-        $this->assertEquals(Border::LINE_SINGLE, $object->getLineStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineStyle(''));
-        $this->assertEquals(Border::LINE_SINGLE, $object->getLineStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineStyle(BORDER::LINE_DOUBLE));
-        $this->assertEquals(Border::LINE_DOUBLE, $object->getLineStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineStyle());
+        self::assertEquals(Border::LINE_SINGLE, $object->getLineStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineStyle(''));
+        self::assertEquals(Border::LINE_SINGLE, $object->getLineStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineStyle(BORDER::LINE_DOUBLE));
+        self::assertEquals(Border::LINE_DOUBLE, $object->getLineStyle());
     }
 
     /**
@@ -102,10 +101,10 @@ public function testSetGetLineStyle(): void
     public function testSetGetLineWidth(): void
     {
         $object = new Border();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineWidth());
-        $this->assertEquals(1, $object->getLineWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineWidth());
+        self::assertEquals(1, $object->getLineWidth());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineWidth($value));
-        $this->assertEquals($value, $object->getLineWidth());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->setLineWidth($value));
+        self::assertEquals($value, $object->getLineWidth());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/BordersTest.php b/tests/PhpPresentation/Tests/Style/BordersTest.php
index 72e9ce8bf4..20fcb28557 100644
--- a/tests/PhpPresentation/Tests/Style/BordersTest.php
+++ b/tests/PhpPresentation/Tests/Style/BordersTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,14 +36,14 @@ class BordersTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Borders();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getBottom());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getLeft());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getRight());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getTop());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getDiagonalDown());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getDiagonalUp());
-        $this->assertEquals(Border::LINE_NONE, $object->getDiagonalDown()->getLineStyle());
-        $this->assertEquals(Border::LINE_NONE, $object->getDiagonalUp()->getLineStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getBottom());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getLeft());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getRight());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getTop());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getDiagonalDown());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Border', $object->getDiagonalUp());
+        self::assertEquals(Border::LINE_NONE, $object->getDiagonalDown()->getLineStyle());
+        self::assertEquals(Border::LINE_NONE, $object->getDiagonalUp()->getLineStyle());
     }
 
     /**
@@ -55,7 +54,7 @@ public function testSetGetHashIndex(): void
         $object = new Borders();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     /**
@@ -64,7 +63,7 @@ public function testSetGetHashIndex(): void
     public function testGetHashCode(): void
     {
         $object = new Borders();
-        $this->assertEquals(
+        self::assertEquals(
             md5(
                 $object->getLeft()->getHashCode() .
                 $object->getRight()->getHashCode() .
diff --git a/tests/PhpPresentation/Tests/Style/BulletTest.php b/tests/PhpPresentation/Tests/Style/BulletTest.php
index 8d8b965630..e884249871 100644
--- a/tests/PhpPresentation/Tests/Style/BulletTest.php
+++ b/tests/PhpPresentation/Tests/Style/BulletTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,11 +36,11 @@ class BulletTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Bullet();
-        $this->assertEquals(Bullet::TYPE_NONE, $object->getBulletType());
-        $this->assertEquals('Calibri', $object->getBulletFont());
-        $this->assertEquals('-', $object->getBulletChar());
-        $this->assertEquals(Bullet::NUMERIC_DEFAULT, $object->getBulletNumericStyle());
-        $this->assertEquals(1, $object->getBulletNumericStartAt());
+        self::assertEquals(Bullet::TYPE_NONE, $object->getBulletType());
+        self::assertEquals('Calibri', $object->getBulletFont());
+        self::assertEquals('-', $object->getBulletChar());
+        self::assertEquals(Bullet::NUMERIC_DEFAULT, $object->getBulletNumericStyle());
+        self::assertEquals(1, $object->getBulletNumericStartAt());
     }
 
     /**
@@ -50,10 +49,10 @@ public function testConstruct(): void
     public function testSetGetBulletChar(): void
     {
         $object = new Bullet();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletChar());
-        $this->assertEquals('-', $object->getBulletChar());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletChar('a'));
-        $this->assertEquals('a', $object->getBulletChar());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletChar());
+        self::assertEquals('-', $object->getBulletChar());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletChar('a'));
+        self::assertEquals('a', $object->getBulletChar());
     }
 
     /**
@@ -66,12 +65,12 @@ public function testSetGetBulletColor(): void
         $expectedARGB = '01234567';
 
         // default
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getBulletColor());
-        $this->assertEquals(Color::COLOR_BLACK, $object->getBulletColor()->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getBulletColor());
+        self::assertEquals(Color::COLOR_BLACK, $object->getBulletColor()->getARGB());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletColor(new Color($expectedARGB)));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getBulletColor());
-        $this->assertEquals($expectedARGB, $object->getBulletColor()->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletColor(new Color($expectedARGB)));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getBulletColor());
+        self::assertEquals($expectedARGB, $object->getBulletColor()->getARGB());
     }
 
     /**
@@ -80,12 +79,12 @@ public function testSetGetBulletColor(): void
     public function testSetGetBulletFont(): void
     {
         $object = new Bullet();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletFont());
-        $this->assertEquals('Calibri', $object->getBulletFont());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletFont(''));
-        $this->assertEquals('Calibri', $object->getBulletFont());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletFont('Arial'));
-        $this->assertEquals('Arial', $object->getBulletFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletFont());
+        self::assertEquals('Calibri', $object->getBulletFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletFont(''));
+        self::assertEquals('Calibri', $object->getBulletFont());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletFont('Arial'));
+        self::assertEquals('Arial', $object->getBulletFont());
     }
 
     /**
@@ -94,11 +93,11 @@ public function testSetGetBulletFont(): void
     public function testSetGetBulletNumericStartAt(): void
     {
         $object = new Bullet();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletNumericStartAt());
-        $this->assertEquals(1, $object->getBulletNumericStartAt());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletNumericStartAt());
+        self::assertEquals(1, $object->getBulletNumericStartAt());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletNumericStartAt($value));
-        $this->assertEquals($value, $object->getBulletNumericStartAt());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletNumericStartAt($value));
+        self::assertEquals($value, $object->getBulletNumericStartAt());
     }
 
     /**
@@ -107,10 +106,10 @@ public function testSetGetBulletNumericStartAt(): void
     public function testSetGetBulletNumericStyle(): void
     {
         $object = new Bullet();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletNumericStyle());
-        $this->assertEquals(Bullet::NUMERIC_DEFAULT, $object->getBulletNumericStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletNumericStyle(Bullet::NUMERIC_ALPHALCPARENBOTH));
-        $this->assertEquals(Bullet::NUMERIC_ALPHALCPARENBOTH, $object->getBulletNumericStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletNumericStyle());
+        self::assertEquals(Bullet::NUMERIC_DEFAULT, $object->getBulletNumericStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletNumericStyle(Bullet::NUMERIC_ALPHALCPARENBOTH));
+        self::assertEquals(Bullet::NUMERIC_ALPHALCPARENBOTH, $object->getBulletNumericStyle());
     }
 
     /**
@@ -119,10 +118,10 @@ public function testSetGetBulletNumericStyle(): void
     public function testSetGetBulletType(): void
     {
         $object = new Bullet();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletType());
-        $this->assertEquals(Bullet::TYPE_NONE, $object->getBulletType());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletType(Bullet::TYPE_BULLET));
-        $this->assertEquals(Bullet::TYPE_BULLET, $object->getBulletType());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletType());
+        self::assertEquals(Bullet::TYPE_NONE, $object->getBulletType());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Bullet', $object->setBulletType(Bullet::TYPE_BULLET));
+        self::assertEquals(Bullet::TYPE_BULLET, $object->getBulletType());
     }
 
     /**
@@ -133,6 +132,6 @@ public function testSetGetHashIndex(): void
         $object = new Bullet();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/ColorMapTest.php b/tests/PhpPresentation/Tests/Style/ColorMapTest.php
index 126c80ac11..8f2ed75806 100644
--- a/tests/PhpPresentation/Tests/Style/ColorMapTest.php
+++ b/tests/PhpPresentation/Tests/Style/ColorMapTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -28,28 +27,28 @@ class ColorMapTest extends TestCase
     public function testConstruct(): void
     {
         $object = new ColorMap();
-        $this->assertIsArray($object->getMapping());
-        $this->assertEquals(ColorMap::$mappingDefault, $object->getMapping());
+        self::assertIsArray($object->getMapping());
+        self::assertEquals(ColorMap::$mappingDefault, $object->getMapping());
     }
 
     public function testMapping(): void
     {
         $object = new ColorMap();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->setMapping([]));
-        $this->assertIsArray($object->getMapping());
-        $this->assertCount(0, $object->getMapping());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->setMapping([]));
+        self::assertIsArray($object->getMapping());
+        self::assertCount(0, $object->getMapping());
         $array = ColorMap::$mappingDefault;
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->setMapping($array));
-        $this->assertIsArray($object->getMapping());
-        $this->assertEquals(ColorMap::$mappingDefault, $object->getMapping());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->setMapping($array));
+        self::assertIsArray($object->getMapping());
+        self::assertEquals(ColorMap::$mappingDefault, $object->getMapping());
     }
 
     public function testModifier(): void
     {
         $object = new ColorMap();
         $key = array_rand(ColorMap::$mappingDefault);
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->changeColor($key, 'AlphaBeta'));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\ColorMap', $object->changeColor($key, 'AlphaBeta'));
         $array = $object->getMapping();
-        $this->assertEquals('AlphaBeta', $array[$key]);
+        self::assertEquals('AlphaBeta', $array[$key]);
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/ColorTest.php b/tests/PhpPresentation/Tests/Style/ColorTest.php
index afdfcd26ac..97485b57dd 100644
--- a/tests/PhpPresentation/Tests/Style/ColorTest.php
+++ b/tests/PhpPresentation/Tests/Style/ColorTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,9 +35,9 @@ class ColorTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Color();
-        $this->assertEquals(Color::COLOR_BLACK, $object->getARGB());
+        self::assertEquals(Color::COLOR_BLACK, $object->getARGB());
         $object = new Color(COLOR::COLOR_BLUE);
-        $this->assertEquals(Color::COLOR_BLUE, $object->getARGB());
+        self::assertEquals(Color::COLOR_BLUE, $object->getARGB());
     }
 
     /**
@@ -48,14 +47,14 @@ public function testAlpha(): void
     {
         $randAlpha = mt_rand(0, 100);
         $object = new Color();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB());
-        $this->assertEquals(100, $object->getAlpha());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB('AA0000FF'));
-        $this->assertEquals(67, $object->getAlpha());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB(Color::COLOR_BLUE));
-        $this->assertEquals(100, $object->getAlpha());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setAlpha($randAlpha));
-        $this->assertEquals($randAlpha, round($object->getAlpha()));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB());
+        self::assertEquals(100, $object->getAlpha());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB('AA0000FF'));
+        self::assertEquals(67, $object->getAlpha());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB(Color::COLOR_BLUE));
+        self::assertEquals(100, $object->getAlpha());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setAlpha($randAlpha));
+        self::assertEquals($randAlpha, round($object->getAlpha()));
     }
 
     /**
@@ -64,12 +63,12 @@ public function testAlpha(): void
     public function testSetGetARGB(): void
     {
         $object = new Color();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB());
-        $this->assertEquals(Color::COLOR_BLACK, $object->getARGB());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB(''));
-        $this->assertEquals(Color::COLOR_BLACK, $object->getARGB());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB(Color::COLOR_BLUE));
-        $this->assertEquals(Color::COLOR_BLUE, $object->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB());
+        self::assertEquals(Color::COLOR_BLACK, $object->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB(''));
+        self::assertEquals(Color::COLOR_BLACK, $object->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setARGB(Color::COLOR_BLUE));
+        self::assertEquals(Color::COLOR_BLUE, $object->getARGB());
     }
 
     /**
@@ -78,18 +77,18 @@ public function testSetGetARGB(): void
     public function testSetGetRGB(): void
     {
         $object = new Color();
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setRGB());
-        $this->assertEquals('000000', $object->getRGB());
-        $this->assertEquals('FF000000', $object->getARGB());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setRGB(''));
-        $this->assertEquals('000000', $object->getRGB());
-        $this->assertEquals('FF000000', $object->getARGB());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setRGB('555'));
-        $this->assertEquals('555', $object->getRGB());
-        $this->assertEquals('FF555', $object->getARGB());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setRGB('6666'));
-        $this->assertEquals('FF6666', $object->getRGB());
-        $this->assertEquals('FF6666', $object->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setRGB());
+        self::assertEquals('000000', $object->getRGB());
+        self::assertEquals('FF000000', $object->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setRGB(''));
+        self::assertEquals('000000', $object->getRGB());
+        self::assertEquals('FF000000', $object->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setRGB('555'));
+        self::assertEquals('555', $object->getRGB());
+        self::assertEquals('FF555', $object->getARGB());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->setRGB('6666'));
+        self::assertEquals('FF6666', $object->getRGB());
+        self::assertEquals('FF6666', $object->getARGB());
     }
 
     /**
@@ -100,6 +99,6 @@ public function testSetGetHashIndex(): void
         $object = new Color();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/FillTest.php b/tests/PhpPresentation/Tests/Style/FillTest.php
index 2ac5eb183d..3430b430ee 100644
--- a/tests/PhpPresentation/Tests/Style/FillTest.php
+++ b/tests/PhpPresentation/Tests/Style/FillTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,12 +36,12 @@ class FillTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Fill();
-        $this->assertEquals(Fill::FILL_NONE, $object->getFillType());
-        $this->assertEquals(0, $object->getRotation());
-        $this->assertInstanceOf(Color::class, $object->getStartColor());
-        $this->assertEquals(Color::COLOR_WHITE, $object->getEndColor()->getARGB());
-        $this->assertInstanceOf(Color::class, $object->getEndColor());
-        $this->assertEquals(Color::COLOR_BLACK, $object->getStartColor()->getARGB());
+        self::assertEquals(Fill::FILL_NONE, $object->getFillType());
+        self::assertEquals(0, $object->getRotation());
+        self::assertInstanceOf(Color::class, $object->getStartColor());
+        self::assertEquals(Color::COLOR_WHITE, $object->getEndColor()->getARGB());
+        self::assertInstanceOf(Color::class, $object->getEndColor());
+        self::assertEquals(Color::COLOR_BLACK, $object->getStartColor()->getARGB());
     }
 
     /**
@@ -51,9 +50,9 @@ public function testConstruct(): void
     public function testSetGetEndColor(): void
     {
         $object = new Fill();
-        $this->assertInstanceOf(Fill::class, $object->setEndColor(new Color(COLOR::COLOR_BLUE)));
-        $this->assertInstanceOf(Color::class, $object->getEndColor());
-        $this->assertEquals(COLOR::COLOR_BLUE, $object->getEndColor()->getARGB());
+        self::assertInstanceOf(Fill::class, $object->setEndColor(new Color(COLOR::COLOR_BLUE)));
+        self::assertInstanceOf(Color::class, $object->getEndColor());
+        self::assertEquals(COLOR::COLOR_BLUE, $object->getEndColor()->getARGB());
     }
 
     /**
@@ -62,10 +61,10 @@ public function testSetGetEndColor(): void
     public function testSetGetFillType(): void
     {
         $object = new Fill();
-        $this->assertInstanceOf(Fill::class, $object->setFillType());
-        $this->assertEquals(Fill::FILL_NONE, $object->getFillType());
-        $this->assertInstanceOf(Fill::class, $object->setFillType(Fill::FILL_GRADIENT_LINEAR));
-        $this->assertEquals(Fill::FILL_GRADIENT_LINEAR, $object->getFillType());
+        self::assertInstanceOf(Fill::class, $object->setFillType());
+        self::assertEquals(Fill::FILL_NONE, $object->getFillType());
+        self::assertInstanceOf(Fill::class, $object->setFillType(Fill::FILL_GRADIENT_LINEAR));
+        self::assertEquals(Fill::FILL_GRADIENT_LINEAR, $object->getFillType());
     }
 
     /**
@@ -74,11 +73,11 @@ public function testSetGetFillType(): void
     public function testSetGetRotation(): void
     {
         $object = new Fill();
-        $this->assertInstanceOf(Fill::class, $object->setRotation());
-        $this->assertEquals(0, $object->getRotation());
+        self::assertInstanceOf(Fill::class, $object->setRotation());
+        self::assertEquals(0, $object->getRotation());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Fill::class, $object->setRotation($value));
-        $this->assertEquals($value, $object->getRotation());
+        self::assertInstanceOf(Fill::class, $object->setRotation($value));
+        self::assertEquals($value, $object->getRotation());
     }
 
     /**
@@ -87,9 +86,9 @@ public function testSetGetRotation(): void
     public function testSetGetStartColor(): void
     {
         $object = new Fill();
-        $this->assertInstanceOf(Fill::class, $object->setStartColor(new Color(COLOR::COLOR_BLUE)));
-        $this->assertInstanceOf(Color::class, $object->getStartColor());
-        $this->assertEquals(COLOR::COLOR_BLUE, $object->getStartColor()->getARGB());
+        self::assertInstanceOf(Fill::class, $object->setStartColor(new Color(COLOR::COLOR_BLUE)));
+        self::assertInstanceOf(Color::class, $object->getStartColor());
+        self::assertEquals(COLOR::COLOR_BLUE, $object->getStartColor()->getARGB());
     }
 
     /**
@@ -100,6 +99,6 @@ public function testSetGetHashIndex(): void
         $object = new Fill();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/FontTest.php b/tests/PhpPresentation/Tests/Style/FontTest.php
index 47deb3f0ba..1237238a36 100644
--- a/tests/PhpPresentation/Tests/Style/FontTest.php
+++ b/tests/PhpPresentation/Tests/Style/FontTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,17 +36,17 @@ class FontTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Font();
-        $this->assertEquals('Calibri', $object->getName());
-        $this->assertEquals(10, $object->getSize());
-        $this->assertFalse($object->isBold());
-        $this->assertFalse($object->isItalic());
-        $this->assertFalse($object->isSuperScript());
-        $this->assertFalse($object->isSubScript());
-        $this->assertFalse($object->isStrikethrough());
-        $this->assertEquals(Font::UNDERLINE_NONE, $object->getUnderline());
-        $this->assertEquals(0, $object->getCharacterSpacing());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
-        $this->assertEquals(Color::COLOR_BLACK, $object->getColor()->getARGB());
+        self::assertEquals('Calibri', $object->getName());
+        self::assertEquals(10, $object->getSize());
+        self::assertFalse($object->isBold());
+        self::assertFalse($object->isItalic());
+        self::assertFalse($object->isSuperScript());
+        self::assertFalse($object->isSubScript());
+        self::assertFalse($object->isStrikethrough());
+        self::assertEquals(Font::UNDERLINE_NONE, $object->getUnderline());
+        self::assertEquals(0, $object->getCharacterSpacing());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
+        self::assertEquals(Color::COLOR_BLACK, $object->getColor()->getARGB());
     }
 
     /**
@@ -56,13 +55,13 @@ public function testConstruct(): void
     public function testCharacterSpacing(): void
     {
         $object = new Font();
-        $this->assertEquals(0, $object->getCharacterSpacing());
-        $this->assertInstanceOf(Font::class, $object->setCharacterSpacing(0));
-        $this->assertEquals(0, $object->getCharacterSpacing());
-        $this->assertInstanceOf(Font::class, $object->setCharacterSpacing(10));
-        $this->assertEquals(1000, $object->getCharacterSpacing());
-        $this->assertInstanceOf(Font::class, $object->setCharacterSpacing());
-        $this->assertEquals(0, $object->getCharacterSpacing());
+        self::assertEquals(0, $object->getCharacterSpacing());
+        self::assertInstanceOf(Font::class, $object->setCharacterSpacing(0));
+        self::assertEquals(0, $object->getCharacterSpacing());
+        self::assertInstanceOf(Font::class, $object->setCharacterSpacing(10));
+        self::assertEquals(1000, $object->getCharacterSpacing());
+        self::assertInstanceOf(Font::class, $object->setCharacterSpacing());
+        self::assertEquals(0, $object->getCharacterSpacing());
     }
 
     /**
@@ -71,10 +70,10 @@ public function testCharacterSpacing(): void
     public function testColor(): void
     {
         $object = new Font();
-        $this->assertEquals(Color::COLOR_BLACK, $object->getColor()->getARGB());
-        $this->assertInstanceOf(Font::class, $object->setColor(new Color(Color::COLOR_BLUE)));
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
-        $this->assertEquals(Color::COLOR_BLUE, $object->getColor()->getARGB());
+        self::assertEquals(Color::COLOR_BLACK, $object->getColor()->getARGB());
+        self::assertInstanceOf(Font::class, $object->setColor(new Color(Color::COLOR_BLUE)));
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\Color', $object->getColor());
+        self::assertEquals(Color::COLOR_BLUE, $object->getColor()->getARGB());
     }
 
     /**
@@ -83,15 +82,15 @@ public function testColor(): void
     public function testFormat(): void
     {
         $object = new Font();
-        $this->assertEquals(Font::FORMAT_LATIN, $object->getFormat());
-        $this->assertInstanceOf(Font::class, $object->setFormat());
-        $this->assertEquals(Font::FORMAT_LATIN, $object->getFormat());
-        $this->assertInstanceOf(Font::class, $object->setFormat('UnAuthorized'));
-        $this->assertEquals(Font::FORMAT_LATIN, $object->getFormat());
-        $this->assertInstanceOf(Font::class, $object->setFormat(Font::FORMAT_EAST_ASIAN));
-        $this->assertEquals(Font::FORMAT_EAST_ASIAN, $object->getFormat());
-        $this->assertInstanceOf(Font::class, $object->setFormat(Font::FORMAT_COMPLEX_SCRIPT));
-        $this->assertEquals(Font::FORMAT_COMPLEX_SCRIPT, $object->getFormat());
+        self::assertEquals(Font::FORMAT_LATIN, $object->getFormat());
+        self::assertInstanceOf(Font::class, $object->setFormat());
+        self::assertEquals(Font::FORMAT_LATIN, $object->getFormat());
+        self::assertInstanceOf(Font::class, $object->setFormat('UnAuthorized'));
+        self::assertEquals(Font::FORMAT_LATIN, $object->getFormat());
+        self::assertInstanceOf(Font::class, $object->setFormat(Font::FORMAT_EAST_ASIAN));
+        self::assertEquals(Font::FORMAT_EAST_ASIAN, $object->getFormat());
+        self::assertInstanceOf(Font::class, $object->setFormat(Font::FORMAT_COMPLEX_SCRIPT));
+        self::assertEquals(Font::FORMAT_COMPLEX_SCRIPT, $object->getFormat());
     }
 
     /**
@@ -100,12 +99,12 @@ public function testFormat(): void
     public function testName(): void
     {
         $object = new Font();
-        $this->assertInstanceOf(Font::class, $object->setName());
-        $this->assertEquals('Calibri', $object->getName());
-        $this->assertInstanceOf(Font::class, $object->setName(''));
-        $this->assertEquals('Calibri', $object->getName());
-        $this->assertInstanceOf(Font::class, $object->setName('Arial'));
-        $this->assertEquals('Arial', $object->getName());
+        self::assertInstanceOf(Font::class, $object->setName());
+        self::assertEquals('Calibri', $object->getName());
+        self::assertInstanceOf(Font::class, $object->setName(''));
+        self::assertEquals('Calibri', $object->getName());
+        self::assertInstanceOf(Font::class, $object->setName('Arial'));
+        self::assertEquals('Arial', $object->getName());
     }
 
     /**
@@ -114,11 +113,11 @@ public function testName(): void
     public function testSize(): void
     {
         $object = new Font();
-        $this->assertInstanceOf(Font::class, $object->setSize());
-        $this->assertEquals(10, $object->getSize());
+        self::assertInstanceOf(Font::class, $object->setSize());
+        self::assertEquals(10, $object->getSize());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Font::class, $object->setSize($value));
-        $this->assertEquals($value, $object->getSize());
+        self::assertInstanceOf(Font::class, $object->setSize($value));
+        self::assertEquals($value, $object->getSize());
     }
 
     /**
@@ -127,12 +126,12 @@ public function testSize(): void
     public function testUnderline(): void
     {
         $object = new Font();
-        $this->assertInstanceOf(Font::class, $object->setUnderline());
-        $this->assertEquals(FONT::UNDERLINE_NONE, $object->getUnderline());
-        $this->assertInstanceOf(Font::class, $object->setUnderline(''));
-        $this->assertEquals(FONT::UNDERLINE_NONE, $object->getUnderline());
-        $this->assertInstanceOf(Font::class, $object->setUnderline(FONT::UNDERLINE_DASH));
-        $this->assertEquals(FONT::UNDERLINE_DASH, $object->getUnderline());
+        self::assertInstanceOf(Font::class, $object->setUnderline());
+        self::assertEquals(FONT::UNDERLINE_NONE, $object->getUnderline());
+        self::assertInstanceOf(Font::class, $object->setUnderline(''));
+        self::assertEquals(FONT::UNDERLINE_NONE, $object->getUnderline());
+        self::assertInstanceOf(Font::class, $object->setUnderline(FONT::UNDERLINE_DASH));
+        self::assertEquals(FONT::UNDERLINE_DASH, $object->getUnderline());
     }
 
     /**
@@ -141,12 +140,12 @@ public function testUnderline(): void
     public function testSetIsBold(): void
     {
         $object = new Font();
-        $this->assertInstanceOf(Font::class, $object->setBold());
-        $this->assertFalse($object->isBold());
-        $this->assertInstanceOf(Font::class, $object->setBold(false));
-        $this->assertFalse($object->isBold());
-        $this->assertInstanceOf(Font::class, $object->setBold(true));
-        $this->assertTrue($object->isBold());
+        self::assertInstanceOf(Font::class, $object->setBold());
+        self::assertFalse($object->isBold());
+        self::assertInstanceOf(Font::class, $object->setBold(false));
+        self::assertFalse($object->isBold());
+        self::assertInstanceOf(Font::class, $object->setBold(true));
+        self::assertTrue($object->isBold());
     }
 
     /**
@@ -155,12 +154,12 @@ public function testSetIsBold(): void
     public function testSetIsItalic(): void
     {
         $object = new Font();
-        $this->assertInstanceOf(Font::class, $object->setItalic());
-        $this->assertFalse($object->isItalic());
-        $this->assertInstanceOf(Font::class, $object->setItalic(false));
-        $this->assertFalse($object->isItalic());
-        $this->assertInstanceOf(Font::class, $object->setItalic(true));
-        $this->assertTrue($object->isItalic());
+        self::assertInstanceOf(Font::class, $object->setItalic());
+        self::assertFalse($object->isItalic());
+        self::assertInstanceOf(Font::class, $object->setItalic(false));
+        self::assertFalse($object->isItalic());
+        self::assertInstanceOf(Font::class, $object->setItalic(true));
+        self::assertTrue($object->isItalic());
     }
 
     /**
@@ -169,12 +168,12 @@ public function testSetIsItalic(): void
     public function testSetIsStriketrough(): void
     {
         $object = new Font();
-        $this->assertInstanceOf(Font::class, $object->setStrikethrough());
-        $this->assertFalse($object->isStrikethrough());
-        $this->assertInstanceOf(Font::class, $object->setStrikethrough(false));
-        $this->assertFalse($object->isStrikethrough());
-        $this->assertInstanceOf(Font::class, $object->setStrikethrough(true));
-        $this->assertTrue($object->isStrikethrough());
+        self::assertInstanceOf(Font::class, $object->setStrikethrough());
+        self::assertFalse($object->isStrikethrough());
+        self::assertInstanceOf(Font::class, $object->setStrikethrough(false));
+        self::assertFalse($object->isStrikethrough());
+        self::assertInstanceOf(Font::class, $object->setStrikethrough(true));
+        self::assertTrue($object->isStrikethrough());
     }
 
     /**
@@ -183,25 +182,25 @@ public function testSetIsStriketrough(): void
     public function testSetIsSubScript(): void
     {
         $object = new Font();
-        $this->assertInstanceOf(Font::class, $object->setSubScript());
-        $this->assertFalse($object->isSubScript());
-        $this->assertInstanceOf(Font::class, $object->setSubScript(false));
-        $this->assertFalse($object->isSubScript());
-        $this->assertInstanceOf(Font::class, $object->setSubScript(true));
-        $this->assertTrue($object->isSubScript());
+        self::assertInstanceOf(Font::class, $object->setSubScript());
+        self::assertFalse($object->isSubScript());
+        self::assertInstanceOf(Font::class, $object->setSubScript(false));
+        self::assertFalse($object->isSubScript());
+        self::assertInstanceOf(Font::class, $object->setSubScript(true));
+        self::assertTrue($object->isSubScript());
 
         // Test toggle of SubScript
-        $this->assertInstanceOf(Font::class, $object->setSubScript(false));
-        $this->assertInstanceOf(Font::class, $object->setSuperScript(false));
-        $this->assertFalse($object->isSubScript());
+        self::assertInstanceOf(Font::class, $object->setSubScript(false));
+        self::assertInstanceOf(Font::class, $object->setSuperScript(false));
+        self::assertFalse($object->isSubScript());
 
-        $this->assertInstanceOf(Font::class, $object->setSubScript(true));
-        $this->assertInstanceOf(Font::class, $object->setSuperScript(true));
-        $this->assertFalse($object->isSubScript());
+        self::assertInstanceOf(Font::class, $object->setSubScript(true));
+        self::assertInstanceOf(Font::class, $object->setSuperScript(true));
+        self::assertFalse($object->isSubScript());
 
-        $this->assertInstanceOf(Font::class, $object->setSubScript(true));
-        $this->assertInstanceOf(Font::class, $object->setSuperScript(false));
-        $this->assertTrue($object->isSubScript());
+        self::assertInstanceOf(Font::class, $object->setSubScript(true));
+        self::assertInstanceOf(Font::class, $object->setSuperScript(false));
+        self::assertTrue($object->isSubScript());
     }
 
     /**
@@ -210,25 +209,25 @@ public function testSetIsSubScript(): void
     public function testSetIsSuperScript(): void
     {
         $object = new Font();
-        $this->assertInstanceOf(Font::class, $object->setSuperScript());
-        $this->assertFalse($object->isSuperScript());
-        $this->assertInstanceOf(Font::class, $object->setSuperScript(false));
-        $this->assertFalse($object->isSuperScript());
-        $this->assertInstanceOf(Font::class, $object->setSuperScript(true));
-        $this->assertTrue($object->isSuperScript());
+        self::assertInstanceOf(Font::class, $object->setSuperScript());
+        self::assertFalse($object->isSuperScript());
+        self::assertInstanceOf(Font::class, $object->setSuperScript(false));
+        self::assertFalse($object->isSuperScript());
+        self::assertInstanceOf(Font::class, $object->setSuperScript(true));
+        self::assertTrue($object->isSuperScript());
 
         // Test toggle of SubScript
-        $this->assertInstanceOf(Font::class, $object->setSuperScript(false));
-        $this->assertInstanceOf(Font::class, $object->setSubScript(false));
-        $this->assertFalse($object->isSuperScript());
+        self::assertInstanceOf(Font::class, $object->setSuperScript(false));
+        self::assertInstanceOf(Font::class, $object->setSubScript(false));
+        self::assertFalse($object->isSuperScript());
 
-        $this->assertInstanceOf(Font::class, $object->setSuperScript(true));
-        $this->assertInstanceOf(Font::class, $object->setSubScript(true));
-        $this->assertFalse($object->isSuperScript());
+        self::assertInstanceOf(Font::class, $object->setSuperScript(true));
+        self::assertInstanceOf(Font::class, $object->setSubScript(true));
+        self::assertFalse($object->isSuperScript());
 
-        $this->assertInstanceOf(Font::class, $object->setSuperScript(true));
-        $this->assertInstanceOf(Font::class, $object->setSubScript(false));
-        $this->assertTrue($object->isSuperScript());
+        self::assertInstanceOf(Font::class, $object->setSuperScript(true));
+        self::assertInstanceOf(Font::class, $object->setSubScript(false));
+        self::assertTrue($object->isSuperScript());
     }
 
     /**
@@ -239,6 +238,6 @@ public function testHashIndex(): void
         $object = new Font();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/OutlineTest.php b/tests/PhpPresentation/Tests/Style/OutlineTest.php
index 30411f12b2..340b178efd 100644
--- a/tests/PhpPresentation/Tests/Style/OutlineTest.php
+++ b/tests/PhpPresentation/Tests/Style/OutlineTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,8 +36,8 @@ class OutlineTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Outline();
-        $this->assertEquals(1, $object->getWidth());
-        $this->assertInstanceOf(Fill::class, $object->getFill());
+        self::assertEquals(1, $object->getWidth());
+        self::assertInstanceOf(Fill::class, $object->getFill());
     }
 
     /**
@@ -47,9 +46,9 @@ public function testConstruct(): void
     public function testSetGetFill(): void
     {
         $object = new Outline();
-        $this->assertInstanceOf(Fill::class, $object->getFill());
-        $this->assertInstanceOf(Outline::class, $object->setFill(new Fill()));
-        $this->assertInstanceOf(Fill::class, $object->getFill());
+        self::assertInstanceOf(Fill::class, $object->getFill());
+        self::assertInstanceOf(Outline::class, $object->setFill(new Fill()));
+        self::assertInstanceOf(Fill::class, $object->getFill());
     }
 
     /**
@@ -58,9 +57,9 @@ public function testSetGetFill(): void
     public function testSetGetWidth(): void
     {
         $object = new Outline();
-        $this->assertEquals(1, $object->getWidth());
+        self::assertEquals(1, $object->getWidth());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Outline::class, $object->setWidth($value));
-        $this->assertEquals($value, $object->getWidth());
+        self::assertInstanceOf(Outline::class, $object->setWidth($value));
+        self::assertEquals($value, $object->getWidth());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/ShadowTest.php b/tests/PhpPresentation/Tests/Style/ShadowTest.php
index ec22869827..5e834fd343 100644
--- a/tests/PhpPresentation/Tests/Style/ShadowTest.php
+++ b/tests/PhpPresentation/Tests/Style/ShadowTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,14 +36,14 @@ class ShadowTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Shadow();
-        $this->assertFalse($object->isVisible());
-        $this->assertEquals(6, $object->getBlurRadius());
-        $this->assertEquals(2, $object->getDistance());
-        $this->assertEquals(0, $object->getDirection());
-        $this->assertEquals(Shadow::SHADOW_BOTTOM_RIGHT, $object->getAlignment());
-        $this->assertInstanceOf(Color::class, $object->getColor());
-        $this->assertEquals(Color::COLOR_BLACK, $object->getColor()->getARGB());
-        $this->assertEquals(50, $object->getAlpha());
+        self::assertFalse($object->isVisible());
+        self::assertEquals(6, $object->getBlurRadius());
+        self::assertEquals(2, $object->getDistance());
+        self::assertEquals(0, $object->getDirection());
+        self::assertEquals(Shadow::SHADOW_BOTTOM_RIGHT, $object->getAlignment());
+        self::assertInstanceOf(Color::class, $object->getColor());
+        self::assertEquals(Color::COLOR_BLACK, $object->getColor()->getARGB());
+        self::assertEquals(50, $object->getAlpha());
     }
 
     /**
@@ -53,10 +52,10 @@ public function testConstruct(): void
     public function testSetGetAlignment(): void
     {
         $object = new Shadow();
-        $this->assertInstanceOf(Shadow::class, $object->setAlignment());
-        $this->assertEquals(Shadow::SHADOW_BOTTOM_RIGHT, $object->getAlignment());
-        $this->assertInstanceOf(Shadow::class, $object->setAlignment(Shadow::SHADOW_CENTER));
-        $this->assertEquals(Shadow::SHADOW_CENTER, $object->getAlignment());
+        self::assertInstanceOf(Shadow::class, $object->setAlignment());
+        self::assertEquals(Shadow::SHADOW_BOTTOM_RIGHT, $object->getAlignment());
+        self::assertInstanceOf(Shadow::class, $object->setAlignment(Shadow::SHADOW_CENTER));
+        self::assertEquals(Shadow::SHADOW_CENTER, $object->getAlignment());
     }
 
     /**
@@ -65,11 +64,11 @@ public function testSetGetAlignment(): void
     public function testSetGetAlpha(): void
     {
         $object = new Shadow();
-        $this->assertInstanceOf(Shadow::class, $object->setAlpha());
-        $this->assertEquals(0, $object->getAlpha());
+        self::assertInstanceOf(Shadow::class, $object->setAlpha());
+        self::assertEquals(0, $object->getAlpha());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Shadow::class, $object->setAlpha($value));
-        $this->assertEquals($value, $object->getAlpha());
+        self::assertInstanceOf(Shadow::class, $object->setAlpha($value));
+        self::assertEquals($value, $object->getAlpha());
     }
 
     /**
@@ -78,11 +77,11 @@ public function testSetGetAlpha(): void
     public function testSetGetBlurRadius(): void
     {
         $object = new Shadow();
-        $this->assertInstanceOf(Shadow::class, $object->setBlurRadius());
-        $this->assertEquals(6, $object->getBlurRadius());
+        self::assertInstanceOf(Shadow::class, $object->setBlurRadius());
+        self::assertEquals(6, $object->getBlurRadius());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Shadow::class, $object->setBlurRadius($value));
-        $this->assertEquals($value, $object->getBlurRadius());
+        self::assertInstanceOf(Shadow::class, $object->setBlurRadius($value));
+        self::assertEquals($value, $object->getBlurRadius());
     }
 
     /**
@@ -91,11 +90,11 @@ public function testSetGetBlurRadius(): void
     public function testSetGetColor(): void
     {
         $object = new Shadow();
-        $this->assertInstanceOf(Shadow::class, $object->setColor());
-        $this->assertNull($object->getColor());
-        $this->assertInstanceOf(Shadow::class, $object->setColor(new Color(Color::COLOR_BLUE)));
-        $this->assertInstanceOf(Color::class, $object->getColor());
-        $this->assertEquals(Color::COLOR_BLUE, $object->getColor()->getARGB());
+        self::assertInstanceOf(Shadow::class, $object->setColor());
+        self::assertNull($object->getColor());
+        self::assertInstanceOf(Shadow::class, $object->setColor(new Color(Color::COLOR_BLUE)));
+        self::assertInstanceOf(Color::class, $object->getColor());
+        self::assertEquals(Color::COLOR_BLUE, $object->getColor()->getARGB());
     }
 
     /**
@@ -104,11 +103,11 @@ public function testSetGetColor(): void
     public function testSetGetDirection(): void
     {
         $object = new Shadow();
-        $this->assertInstanceOf(Shadow::class, $object->setDirection());
-        $this->assertEquals(0, $object->getDirection());
+        self::assertInstanceOf(Shadow::class, $object->setDirection());
+        self::assertEquals(0, $object->getDirection());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Shadow::class, $object->setDirection($value));
-        $this->assertEquals($value, $object->getDirection());
+        self::assertInstanceOf(Shadow::class, $object->setDirection($value));
+        self::assertEquals($value, $object->getDirection());
     }
 
     /**
@@ -117,11 +116,11 @@ public function testSetGetDirection(): void
     public function testSetGetDistance(): void
     {
         $object = new Shadow();
-        $this->assertInstanceOf(Shadow::class, $object->setDistance());
-        $this->assertEquals(2, $object->getDistance());
+        self::assertInstanceOf(Shadow::class, $object->setDistance());
+        self::assertEquals(2, $object->getDistance());
         $value = mt_rand(1, 100);
-        $this->assertInstanceOf(Shadow::class, $object->setDistance($value));
-        $this->assertEquals($value, $object->getDistance());
+        self::assertInstanceOf(Shadow::class, $object->setDistance($value));
+        self::assertEquals($value, $object->getDistance());
     }
 
     /**
@@ -132,7 +131,7 @@ public function testSetGetHashIndex(): void
         $object = new Shadow();
         $value = mt_rand(1, 100);
         $object->setHashIndex($value);
-        $this->assertEquals($value, $object->getHashIndex());
+        self::assertEquals($value, $object->getHashIndex());
     }
 
     /**
@@ -141,11 +140,11 @@ public function testSetGetHashIndex(): void
     public function testSetIsVisible(): void
     {
         $object = new Shadow();
-        $this->assertInstanceOf(Shadow::class, $object->setVisible());
-        $this->assertFalse($object->isVisible());
-        $this->assertInstanceOf(Shadow::class, $object->setVisible(false));
-        $this->assertFalse($object->isVisible());
-        $this->assertInstanceOf(Shadow::class, $object->setVisible(true));
-        $this->assertTrue($object->isVisible());
+        self::assertInstanceOf(Shadow::class, $object->setVisible());
+        self::assertFalse($object->isVisible());
+        self::assertInstanceOf(Shadow::class, $object->setVisible(false));
+        self::assertFalse($object->isVisible());
+        self::assertInstanceOf(Shadow::class, $object->setVisible(true));
+        self::assertTrue($object->isVisible());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Style/TextStyleTest.php b/tests/PhpPresentation/Tests/Style/TextStyleTest.php
index b85da8f1fe..a021c09d7d 100644
--- a/tests/PhpPresentation/Tests/Style/TextStyleTest.php
+++ b/tests/PhpPresentation/Tests/Style/TextStyleTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -34,63 +33,63 @@ public function testConstructDefaultTrue(): void
         $object = new TextStyle();
 
         $arrayBodyStyle = $object->getBodyStyle();
-        $this->assertIsArray($arrayBodyStyle);
-        $this->assertCount(1, $arrayBodyStyle);
-        $this->assertArrayHasKey(1, $arrayBodyStyle);
-        $this->assertNull($object->getBodyStyleAtLvl(0));
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getBodyStyleAtLvl(1));
+        self::assertIsArray($arrayBodyStyle);
+        self::assertCount(1, $arrayBodyStyle);
+        self::assertArrayHasKey(1, $arrayBodyStyle);
+        self::assertNull($object->getBodyStyleAtLvl(0));
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getBodyStyleAtLvl(1));
         $oParagraph = $object->getBodyStyleAtLvl(1);
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $oParagraph);
-        $this->assertEquals(Alignment::HORIZONTAL_CENTER, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals((-324900 / 9525), $oParagraph->getAlignment()->getIndent());
-        $this->assertEquals(0, $oParagraph->getAlignment()->getMarginLeft());
-        $this->assertEquals(32, $oParagraph->getFont()->getSize());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $oParagraph);
+        self::assertEquals(Alignment::HORIZONTAL_CENTER, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals((-324900 / 9525), $oParagraph->getAlignment()->getIndent());
+        self::assertEquals(0, $oParagraph->getAlignment()->getMarginLeft());
+        self::assertEquals(32, $oParagraph->getFont()->getSize());
         /** @var SchemeColor $color */
         $color = $oParagraph->getFont()->getColor();
-        $this->assertInstanceOf(SchemeColor::class, $color);
-        $this->assertEquals('tx1', $color->getValue());
+        self::assertInstanceOf(SchemeColor::class, $color);
+        self::assertEquals('tx1', $color->getValue());
 
         $arrayOtherStyle = $object->getOtherStyle();
-        $this->assertIsArray($arrayOtherStyle);
-        $this->assertCount(1, $arrayOtherStyle);
-        $this->assertArrayHasKey(0, $arrayOtherStyle);
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getOtherStyleAtLvl(0));
-        $this->assertNull($object->getOtherStyleAtLvl(1));
+        self::assertIsArray($arrayOtherStyle);
+        self::assertCount(1, $arrayOtherStyle);
+        self::assertArrayHasKey(0, $arrayOtherStyle);
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getOtherStyleAtLvl(0));
+        self::assertNull($object->getOtherStyleAtLvl(1));
         $oParagraph = $object->getOtherStyleAtLvl(0);
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $oParagraph);
-        $this->assertEquals(Alignment::HORIZONTAL_CENTER, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(10, $oParagraph->getFont()->getSize());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $oParagraph);
+        self::assertEquals(Alignment::HORIZONTAL_CENTER, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(10, $oParagraph->getFont()->getSize());
         /** @var SchemeColor $color */
         $color = $oParagraph->getFont()->getColor();
-        $this->assertInstanceOf(SchemeColor::class, $color);
-        $this->assertEquals('tx1', $color->getValue());
+        self::assertInstanceOf(SchemeColor::class, $color);
+        self::assertEquals('tx1', $color->getValue());
 
         $arrayTitleStyle = $object->getTitleStyle();
-        $this->assertIsArray($arrayTitleStyle);
-        $this->assertCount(1, $arrayTitleStyle);
-        $this->assertArrayHasKey(1, $arrayTitleStyle);
-        $this->assertNull($object->getTitleStyleAtLvl(0));
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getTitleStyleAtLvl(1));
+        self::assertIsArray($arrayTitleStyle);
+        self::assertCount(1, $arrayTitleStyle);
+        self::assertArrayHasKey(1, $arrayTitleStyle);
+        self::assertNull($object->getTitleStyleAtLvl(0));
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getTitleStyleAtLvl(1));
         $oParagraph = $object->getTitleStyleAtLvl(1);
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $oParagraph);
-        $this->assertEquals(Alignment::HORIZONTAL_CENTER, $oParagraph->getAlignment()->getHorizontal());
-        $this->assertEquals(44, $oParagraph->getFont()->getSize());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $oParagraph);
+        self::assertEquals(Alignment::HORIZONTAL_CENTER, $oParagraph->getAlignment()->getHorizontal());
+        self::assertEquals(44, $oParagraph->getFont()->getSize());
         /** @var SchemeColor $color */
         $color = $oParagraph->getFont()->getColor();
-        $this->assertInstanceOf(SchemeColor::class, $color);
-        $this->assertEquals('lt1', $color->getValue());
+        self::assertInstanceOf(SchemeColor::class, $color);
+        self::assertEquals('lt1', $color->getValue());
     }
 
     public function testConstructDefaultFalse(): void
     {
         $object = new TextStyle(false);
 
-        $this->assertIsArray($object->getBodyStyle());
-        $this->assertCount(0, $object->getBodyStyle());
-        $this->assertIsArray($object->getOtherStyle());
-        $this->assertCount(0, $object->getOtherStyle());
-        $this->assertIsArray($object->getTitleStyle());
-        $this->assertCount(0, $object->getTitleStyle());
+        self::assertIsArray($object->getBodyStyle());
+        self::assertCount(0, $object->getBodyStyle());
+        self::assertIsArray($object->getOtherStyle());
+        self::assertCount(0, $object->getOtherStyle());
+        self::assertIsArray($object->getTitleStyle());
+        self::assertCount(0, $object->getTitleStyle());
     }
 
     public function testLevel(): void
@@ -99,34 +98,34 @@ public function testLevel(): void
         $object = new TextStyle(false);
         $oParagraph = new Paragraph();
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setBodyStyleAtLvl($oParagraph, null));
-        $this->assertNull($object->getBodyStyleAtLvl(null));
-        $this->assertCount(0, $object->getBodyStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setBodyStyleAtLvl($oParagraph, 10));
-        $this->assertNull($object->getBodyStyleAtLvl(10));
-        $this->assertCount(0, $object->getBodyStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setBodyStyleAtLvl($oParagraph, $value));
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getBodyStyleAtLvl($value));
-        $this->assertCount(1, $object->getBodyStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setBodyStyleAtLvl($oParagraph, null));
+        self::assertNull($object->getBodyStyleAtLvl(null));
+        self::assertCount(0, $object->getBodyStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setBodyStyleAtLvl($oParagraph, 10));
+        self::assertNull($object->getBodyStyleAtLvl(10));
+        self::assertCount(0, $object->getBodyStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setBodyStyleAtLvl($oParagraph, $value));
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getBodyStyleAtLvl($value));
+        self::assertCount(1, $object->getBodyStyle());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setOtherStyleAtLvl($oParagraph, null));
-        $this->assertNull($object->getOtherStyleAtLvl(null));
-        $this->assertCount(0, $object->getOtherStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setOtherStyleAtLvl($oParagraph, 10));
-        $this->assertNull($object->getOtherStyleAtLvl(10));
-        $this->assertCount(0, $object->getOtherStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setOtherStyleAtLvl($oParagraph, $value));
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getOtherStyleAtLvl($value));
-        $this->assertCount(1, $object->getOtherStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setOtherStyleAtLvl($oParagraph, null));
+        self::assertNull($object->getOtherStyleAtLvl(null));
+        self::assertCount(0, $object->getOtherStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setOtherStyleAtLvl($oParagraph, 10));
+        self::assertNull($object->getOtherStyleAtLvl(10));
+        self::assertCount(0, $object->getOtherStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setOtherStyleAtLvl($oParagraph, $value));
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getOtherStyleAtLvl($value));
+        self::assertCount(1, $object->getOtherStyle());
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setTitleStyleAtLvl($oParagraph, null));
-        $this->assertNull($object->getTitleStyleAtLvl(null));
-        $this->assertCount(0, $object->getTitleStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setTitleStyleAtLvl($oParagraph, 10));
-        $this->assertNull($object->getTitleStyleAtLvl(10));
-        $this->assertCount(0, $object->getTitleStyle());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setTitleStyleAtLvl($oParagraph, $value));
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getTitleStyleAtLvl($value));
-        $this->assertCount(1, $object->getTitleStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setTitleStyleAtLvl($oParagraph, null));
+        self::assertNull($object->getTitleStyleAtLvl(null));
+        self::assertCount(0, $object->getTitleStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setTitleStyleAtLvl($oParagraph, 10));
+        self::assertNull($object->getTitleStyleAtLvl(10));
+        self::assertCount(0, $object->getTitleStyle());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\Style\\TextStyle', $object->setTitleStyleAtLvl($oParagraph, $value));
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\RichText\Paragraph', $object->getTitleStyleAtLvl($value));
+        self::assertCount(1, $object->getTitleStyle());
     }
 }
diff --git a/tests/PhpPresentation/Tests/Writer/AbstractWriter.php b/tests/PhpPresentation/Tests/Writer/AbstractWriter.php
index 7da382b974..a54b7d929e 100644
--- a/tests/PhpPresentation/Tests/Writer/AbstractWriter.php
+++ b/tests/PhpPresentation/Tests/Writer/AbstractWriter.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -32,8 +31,6 @@ class AbstractWriter extends Writer\AbstractWriter
      * public wrapper for protected method.
      *
      * @return AbstractShape[] All drawings in PhpPresentation
-     *
-     * @throws \Exception
      */
     public function allDrawings(): array
     {
diff --git a/tests/PhpPresentation/Tests/Writer/AbstractWriterTest.php b/tests/PhpPresentation/Tests/Writer/AbstractWriterTest.php
index 101ed117ca..4dfbd2b042 100644
--- a/tests/PhpPresentation/Tests/Writer/AbstractWriterTest.php
+++ b/tests/PhpPresentation/Tests/Writer/AbstractWriterTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -45,9 +44,9 @@ public function testConstruct(): void
         /** @var ZipInterface $oStubZip */
         $oStubZip = $this->getMockForAbstractClass(ZipInterface::class);
 
-        $this->assertNull($oStubWriter->getZipAdapter());
-        $this->assertInstanceOf(AbstractWriter::class, $oStubWriter->setZipAdapter($oStubZip));
-        $this->assertInstanceOf(ZipInterface::class, $oStubWriter->getZipAdapter());
+        self::assertNull($oStubWriter->getZipAdapter());
+        self::assertInstanceOf(AbstractWriter::class, $oStubWriter->setZipAdapter($oStubZip));
+        self::assertInstanceOf(ZipInterface::class, $oStubWriter->getZipAdapter());
     }
 
     /**
@@ -69,6 +68,6 @@ public function testAllDrawingsIncludesMasterSlides(): void
         $writer->setPhpPresentation($presentation);
 
         $drawings = $writer->allDrawings();
-        $this->assertCount(2, $drawings, 'Number of drawings should equal two: one from normal slide and one from master slide');
+        self::assertCount(2, $drawings, 'Number of drawings should equal two: one from normal slide and one from master slide');
     }
 }
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/ContentTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/ContentTest.php
index c67a78bc96..6ec41135c5 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/ContentTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/ContentTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,6 +35,7 @@
 use PhpOffice\PhpPresentation\Style\Fill;
 use PhpOffice\PhpPresentation\Style\Font;
 use PhpOffice\PhpPresentation\Tests\PhpPresentationTestCase;
+use ReflectionClass;
 
 /**
  * Test class for PhpOffice\PhpPresentation\Writer\ODPresentation\Manifest.
@@ -118,7 +118,7 @@ public function testDrawingShapeFill(): void
         $this->assertIsSchemaOpenDocumentNotValid('1.2');
 
         $oColor = new Color(Color::COLOR_DARKRED);
-        $oColor->setAlpha(rand(0, 100));
+        $oColor->setAlpha(mt_rand(0, 100));
         $oShape->getFill()->setFillType(Fill::FILL_SOLID)->setStartColor($oColor);
         $this->resetPresentationFile();
 
@@ -539,7 +539,7 @@ public function testRichTextShadow(): void
             if (0 == $inc || 180 == $inc || 360 == $inc) {
                 $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-y', '0cm');
             } else {
-                if (($inc > 0 && $inc < 180) || 360 == $inc) {
+                if ($inc < 180) {
                     $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-y', Drawing::pixelsToCentimeters((int) $randDistance) . 'cm');
                 } else {
                     $this->assertZipXmlAttributeEquals('content.xml', $element, 'draw:shadow-offset-y', '-' . Drawing::pixelsToCentimeters((int) $randDistance) . 'cm');
@@ -989,7 +989,7 @@ public function testTransition(): void
         $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-speed', 'slow');
         $this->assertIsSchemaOpenDocumentValid('1.2');
 
-        $rcTransition = new \ReflectionClass('PhpOffice\PhpPresentation\Slide\Transition');
+        $rcTransition = new ReflectionClass('PhpOffice\PhpPresentation\Slide\Transition');
         $arrayConstants = $rcTransition->getConstants();
         foreach ($arrayConstants as $key => $value) {
             if (0 !== strpos($key, 'TRANSITION_')) {
@@ -1001,147 +1001,195 @@ public function testTransition(): void
             switch ($key) {
                 case 'TRANSITION_BLINDS_HORIZONTAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'horizontal-stripes');
+
                     break;
                 case 'TRANSITION_BLINDS_VERTICAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'vertical-stripes');
+
                     break;
                 case 'TRANSITION_CHECKER_HORIZONTAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'horizontal-checkerboard');
+
                     break;
                 case 'TRANSITION_CHECKER_VERTICAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'vertical-checkerboard');
+
                     break;
                 case 'TRANSITION_CIRCLE_HORIZONTAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_CIRCLE_VERTICAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_COMB_HORIZONTAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_COMB_VERTICAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_COVER_DOWN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'uncover-to-bottom');
+
                     break;
                 case 'TRANSITION_COVER_LEFT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'uncover-to-left');
+
                     break;
                 case 'TRANSITION_COVER_LEFT_DOWN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'uncover-to-lowerleft');
+
                     break;
                 case 'TRANSITION_COVER_LEFT_UP':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'uncover-to-upperleft');
+
                     break;
                 case 'TRANSITION_COVER_RIGHT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'uncover-to-right');
+
                     break;
                 case 'TRANSITION_COVER_RIGHT_DOWN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'uncover-to-lowerright');
+
                     break;
                 case 'TRANSITION_COVER_RIGHT_UP':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'uncover-to-upperright');
+
                     break;
                 case 'TRANSITION_COVER_UP':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'uncover-to-top');
+
                     break;
                 case 'TRANSITION_CUT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_DIAMOND':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_DISSOLVE':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'dissolve');
+
                     break;
                 case 'TRANSITION_FADE':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'fade-from-center');
+
                     break;
                 case 'TRANSITION_NEWSFLASH':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_PLUS':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'close');
+
                     break;
                 case 'TRANSITION_PULL_DOWN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'stretch-from-bottom');
+
                     break;
                 case 'TRANSITION_PULL_LEFT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'stretch-from-left');
+
                     break;
                 case 'TRANSITION_PULL_RIGHT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'stretch-from-right');
+
                     break;
                 case 'TRANSITION_PULL_UP':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'stretch-from-top');
+
                     break;
                 case 'TRANSITION_PUSH_DOWN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'roll-from-bottom');
+
                     break;
                 case 'TRANSITION_PUSH_LEFT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'roll-from-left');
+
                     break;
                 case 'TRANSITION_PUSH_RIGHT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'roll-from-right');
+
                     break;
                 case 'TRANSITION_PUSH_UP':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'roll-from-top');
+
                     break;
                 case 'TRANSITION_RANDOM':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'random');
+
                     break;
                 case 'TRANSITION_RANDOMBAR_HORIZONTAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'horizontal-lines');
+
                     break;
                 case 'TRANSITION_RANDOMBAR_VERTICAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'vertical-lines');
+
                     break;
                 case 'TRANSITION_SPLIT_IN_HORIZONTAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'close-horizontal');
+
                     break;
                 case 'TRANSITION_SPLIT_OUT_HORIZONTAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'open-horizontal');
+
                     break;
                 case 'TRANSITION_SPLIT_IN_VERTICAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'close-vertical');
+
                     break;
                 case 'TRANSITION_SPLIT_OUT_VERTICAL':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'open-vertical');
+
                     break;
                 case 'TRANSITION_STRIPS_LEFT_DOWN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_STRIPS_LEFT_UP':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_STRIPS_RIGHT_DOWN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_STRIPS_RIGHT_UP':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_WEDGE':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_WIPE_DOWN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'fade-from-bottom');
+
                     break;
                 case 'TRANSITION_WIPE_LEFT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'fade-from-left');
+
                     break;
                 case 'TRANSITION_WIPE_RIGHT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'fade-from-right');
+
                     break;
                 case 'TRANSITION_WIPE_UP':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'fade-from-top');
+
                     break;
                 case 'TRANSITION_ZOOM_IN':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
                 case 'TRANSITION_ZOOM_OUT':
                     $this->assertZipXmlAttributeContains('content.xml', $element, 'presentation:transition-style', 'none');
+
                     break;
             }
             $this->assertIsSchemaOpenDocumentValid('1.2');
@@ -1192,7 +1240,7 @@ public function testShowType(string $slideshowType, bool $withAttribute): void
     }
 
     /**
-     * @return array<array<string|bool>>
+     * @return array<array<bool|string>>
      */
     public function dataProviderShowType(): array
     {
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaInfManifestTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaInfManifestTest.php
index 6019d6666e..223330864a 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaInfManifestTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaInfManifestTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaTest.php
index a6a142e699..73e68a3cec 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/MetaTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -31,9 +30,6 @@ class MetaTest extends PhpPresentationTestCase
      * @dataProvider dataProviderCustomProperties
      *
      * @param mixed $propertyValue
-     * @param string|null $propertyType
-     * @param string $expectedValue
-     * @param string $expectedValueType
      */
     public function testCustomProperties($propertyValue, ?string $propertyType, string $expectedValue, string $expectedValueType): void
     {
@@ -50,7 +46,7 @@ public function testCustomProperties($propertyValue, ?string $propertyType, stri
     }
 
     /**
-     * @return array<array<bool|string|int|float|null>>
+     * @return array<array<null|bool|float|int|string>>
      */
     public function dataProviderCustomProperties(): array
     {
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/ObjectsChartTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/ObjectsChartTest.php
index 59e668c8ae..af4df52104 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/ObjectsChartTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/ObjectsChartTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -95,8 +94,7 @@ public function testAxisFont(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'fo:font-size', '16pt');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'fo:font-family', 'Arial');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testAxisTitleRotation(): void
@@ -115,10 +113,9 @@ public function testAxisTitleRotation(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'style:rotation-angle');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
-        $value = rand(1, 360);
+        $value = mt_rand(1, 360);
         $oShape->getPlotArea()->getAxisX()->setTitleRotation($value);
         $this->resetPresentationFile();
 
@@ -127,8 +124,7 @@ public function testAxisTitleRotation(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'style:rotation-angle');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'style:rotation-angle', '-' . $value);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testAxisVisibility(): void
@@ -156,8 +152,7 @@ public function testAxisVisibility(): void
 
         $this->assertZipXmlElementNotExists('Object 1/content.xml', $element);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oShape->getPlotArea()->getAxisX()->setIsVisible(true);
         $oShape->getPlotArea()->getAxisY()->setIsVisible(true);
@@ -183,8 +178,7 @@ public function testAxisVisibility(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlElementEquals('Object 1/content.xml', $element, 'Axis Y');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testChartDisplayBlankAs(): void
@@ -203,8 +197,7 @@ public function testChartDisplayBlankAs(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:treat-empty-cells');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:treat-empty-cells', 'use-zero');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
         $oShape->setDisplayBlankAs(Chart::BLANKAS_SPAN);
@@ -213,8 +206,7 @@ public function testChartDisplayBlankAs(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:treat-empty-cells');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:treat-empty-cells', 'ignore');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
         $oShape->setDisplayBlankAs(Chart::BLANKAS_GAP);
@@ -223,8 +215,7 @@ public function testChartDisplayBlankAs(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:treat-empty-cells');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:treat-empty-cells', 'leave-gap');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testLegend(): void
@@ -250,8 +241,7 @@ public function testLegend(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $element = '/office:document-content/office:body/office:chart/chart:chart/table:table/table:table-header-rows/table:table-row/table:table-cell[@office:value-type=\'string\']';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oChart->getLegend()->setPosition(Legend::POSITION_RIGHT);
         $this->resetPresentationFile();
@@ -259,8 +249,7 @@ public function testLegend(): void
         $element = '/office:document-content/office:body/office:chart/chart:chart/chart:legend';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:legend-position', 'end');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oChart->getLegend()->setPosition(Legend::POSITION_LEFT);
         $this->resetPresentationFile();
@@ -268,8 +257,7 @@ public function testLegend(): void
         $element = '/office:document-content/office:body/office:chart/chart:chart/chart:legend';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:legend-position', 'start');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oChart->getLegend()->setPosition(Legend::POSITION_BOTTOM);
         $this->resetPresentationFile();
@@ -277,8 +265,7 @@ public function testLegend(): void
         $element = '/office:document-content/office:body/office:chart/chart:chart/chart:legend';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:legend-position', 'bottom');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oChart->getLegend()->setPosition(Legend::POSITION_TOP);
         $this->resetPresentationFile();
@@ -286,8 +273,7 @@ public function testLegend(): void
         $element = '/office:document-content/office:body/office:chart/chart:chart/chart:legend';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:legend-position', 'top');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oChart->getLegend()->setPosition(Legend::POSITION_TOPRIGHT);
         $this->resetPresentationFile();
@@ -295,8 +281,7 @@ public function testLegend(): void
         $element = '/office:document-content/office:body/office:chart/chart:chart/chart:legend';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:legend-position', 'top-end');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testSeriesValues(): void
@@ -321,8 +306,7 @@ public function testSeriesValues(): void
 
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlElementEquals('Object 1/content.xml', $element, 'NaN');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
 
@@ -341,8 +325,7 @@ public function testSeriesValues(): void
 
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlElementEquals('Object 1/content.xml', $element, '12.3');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
 
@@ -360,8 +343,7 @@ public function testSeriesValues(): void
 
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlElementEquals('Object 1/content.xml', $element, 'data');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testSeriesShowConfig(): void
@@ -379,8 +361,7 @@ public function testSeriesShowConfig(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:data-label-number');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:data-label-number', 'value');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:data-label-text');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->setShowValue(false);
         $this->resetPresentationFile();
@@ -389,8 +370,7 @@ public function testSeriesShowConfig(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:data-label-number');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:data-label-text');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         // $showCategoryName = false / $showPercentage = true / $showValue = true
         $oSeries->setShowValue(true);
@@ -401,8 +381,7 @@ public function testSeriesShowConfig(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:data-label-number');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:data-label-number', 'value-and-percentage');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:data-label-text');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         // $showCategoryName = false / $showPercentage = true / $showValue = false
         $oSeries->setShowValue(false);
@@ -412,8 +391,7 @@ public function testSeriesShowConfig(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:data-label-number');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:data-label-number', 'percentage');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:data-label-text');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         // $showCategoryName = false / $showPercentage = true / $showValue = false
         $oSeries->setShowCategoryName(true);
@@ -422,8 +400,7 @@ public function testSeriesShowConfig(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:data-label-text');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:data-label-text', 'true');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTitleVisibility(): void
@@ -435,21 +412,19 @@ public function testTitleVisibility(): void
         $elementTitle = '/office:document-content/office:body/office:chart/chart:chart/chart:title';
         $elementStyle = '/office:document-content/office:automatic-styles/style:style[@style:name=\'styleTitle\']';
 
-        $this->assertTrue($oShape->getTitle()->isVisible());
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Title', $oShape->getTitle()->setVisible(true));
+        self::assertTrue($oShape->getTitle()->isVisible());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Title', $oShape->getTitle()->setVisible(true));
         $this->assertZipXmlElementExists('Object 1/content.xml', $elementTitle);
         $this->assertZipXmlElementExists('Object 1/content.xml', $elementStyle);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Title', $oShape->getTitle()->setVisible(false));
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Title', $oShape->getTitle()->setVisible(false));
         $this->resetPresentationFile();
         $this->assertZipXmlElementNotExists('Object 1/content.xml', $elementTitle);
         $this->assertZipXmlElementNotExists('Object 1/content.xml', $elementStyle);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeArea(): void
@@ -474,8 +449,7 @@ public function testTypeArea(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'draw:fill-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'draw:fill-color', '#93A9CE');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeAxisBounds(): void
@@ -493,8 +467,7 @@ public function testTypeAxisBounds(): void
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:minimum');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:maximum');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oShape->getPlotArea()->getAxisX()->setMinBounds($value);
         $this->resetPresentationFile();
@@ -503,8 +476,7 @@ public function testTypeAxisBounds(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:minimum');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:minimum', $value);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oShape->getPlotArea()->getAxisX()->setMinBounds(null);
         $oShape->getPlotArea()->getAxisX()->setMaxBounds($value);
@@ -514,8 +486,7 @@ public function testTypeAxisBounds(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:maximum');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:maximum', $value);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oShape->getPlotArea()->getAxisX()->setMinBounds($value);
         $oShape->getPlotArea()->getAxisX()->setMaxBounds($value);
@@ -526,8 +497,7 @@ public function testTypeAxisBounds(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:maximum');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:maximum', $value);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeAxisOutline(): void
@@ -547,8 +517,7 @@ public function testTypeAxisOutline(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'svg:stroke-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'svg:stroke-color', '#000000');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
         $shape->getPlotArea()->getAxisX()->getOutline()->setWidth(10);
@@ -562,8 +531,7 @@ public function testTypeAxisOutline(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'svg:stroke-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'svg:stroke-color', '#ABCDEF');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeAxisTickLabelPosition(): void
@@ -581,8 +549,7 @@ public function testTypeAxisTickLabelPosition(): void
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:axis-position');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:tick-mark-position');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
         $oShape->getPlotArea()->getAxisX()->setTickLabelPosition(Axis::TICK_LABEL_POSITION_HIGH);
@@ -593,8 +560,7 @@ public function testTypeAxisTickLabelPosition(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:axis-position', '0');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:tick-mark-position');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
         $oShape->getPlotArea()->getAxisX()->setTickLabelPosition(Axis::TICK_LABEL_POSITION_LOW);
@@ -606,8 +572,7 @@ public function testTypeAxisTickLabelPosition(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:tick-mark-position');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:tick-mark-position', 'at-axis');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeAxisUnit(): void
@@ -625,8 +590,7 @@ public function testTypeAxisUnit(): void
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:interval-minor-divisor');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:interval-major');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $shape->getPlotArea()->getAxisX()->setMinorUnit($value);
         $this->resetPresentationFile();
@@ -635,8 +599,7 @@ public function testTypeAxisUnit(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:interval-minor-divisor');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:interval-minor-divisor', $value);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $shape->getPlotArea()->getAxisX()->setMinorUnit(null);
         $shape->getPlotArea()->getAxisX()->setMajorUnit($value);
@@ -646,8 +609,7 @@ public function testTypeAxisUnit(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:interval-major');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:interval-major', $value);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $shape->getPlotArea()->getAxisX()->setMinorUnit($value);
         $shape->getPlotArea()->getAxisX()->setMajorUnit($value);
@@ -658,8 +620,7 @@ public function testTypeAxisUnit(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:interval-major');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:interval-major', $value);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeBar(): void
@@ -691,8 +652,7 @@ public function testTypeBar(): void
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:percentage');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:data-label-number', 'value');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeBarGroupingStacked(): void
@@ -710,8 +670,7 @@ public function testTypeBarGroupingStacked(): void
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:percentage');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:data-label-number', 'value');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeBarGroupingPercentStacked(): void
@@ -729,8 +688,7 @@ public function testTypeBarGroupingPercentStacked(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:percentage', 'true');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:data-label-number', 'percentage');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeBarHorizontal(): void
@@ -756,8 +714,7 @@ public function testTypeBarHorizontal(): void
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:three-dimensional');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:right-angled-axes');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeBar3D(): void
@@ -787,8 +744,7 @@ public function testTypeBar3D(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:right-angled-axes');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:right-angled-axes', 'true');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeBar3DHorizontal(): void
@@ -816,8 +772,7 @@ public function testTypeBar3DHorizontal(): void
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:right-angled-axes');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:right-angled-axes', 'true');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeDoughnut(): void
@@ -843,8 +798,7 @@ public function testTypeDoughnut(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:class', 'chart:ring');
         $element = '/office:document-content/office:automatic-styles/style:style/style:chart-properties/chart:label-separator/text:p';
         $this->assertZipXmlElementNotExists('Object 1/content.xml', $element);
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         // $oDoughnut->setHoleSize($randHoleSize);
         // $this->resetPresentationFile();
@@ -855,8 +809,7 @@ public function testTypeDoughnut(): void
         $element = '/office:document-content/office:automatic-styles/style:style/style:chart-properties/chart:label-separator/text:p';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlElementEquals('Object 1/content.xml', $element, $randSeparator);
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeLine(): void
@@ -892,8 +845,7 @@ public function testTypeLine(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'svg:stroke-width', '0.035cm');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'svg:stroke-color', '#000000');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeLineGridlines(): void
@@ -961,8 +913,8 @@ public function testTypeLineGridlines(): void
             $this->assertZipXmlAttributeStartsWith('Object 1/content.xml', $expectedElementStyle, 'svg:stroke-color', '#');
             $this->assertZipXmlAttributeEndsWith('Object 1/content.xml', $expectedElementStyle, 'svg:stroke-color', $expectedColor->getRGB());
 
-            // chart:title : Element chart failed to validate attributes
-            $this->assertIsSchemaOpenDocumentNotValid('1.2');
+            // chart:title : 
+            $this->assertIsSchemaOpenDocumentValid('1.2');
         }
     }
 
@@ -991,8 +943,7 @@ public function testTypeLineMarker(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-width', $expectedSizeCm);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-height', $expectedSizeCm);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->getMarker()->setSymbol($expectedSymbol2);
         $oLine->setSeries([$oSeries]);
@@ -1000,8 +951,7 @@ public function testTypeLineMarker(): void
 
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-name', 'horizontal-bar');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->getMarker()->setSymbol($expectedSymbol3);
         $oLine->setSeries([$oSeries]);
@@ -1009,8 +959,7 @@ public function testTypeLineMarker(): void
 
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-name', 'circle');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->getMarker()->setSymbol($expectedSymbol4);
         $oLine->setSeries([$oSeries]);
@@ -1018,8 +967,7 @@ public function testTypeLineMarker(): void
 
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-name', 'arrow-up');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->getMarker()->setSymbol($expectedSymbol5);
         $oLine->setSeries([$oSeries]);
@@ -1029,8 +977,7 @@ public function testTypeLineMarker(): void
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $expectedElement, 'chart:symbol-width');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $expectedElement, 'chart:symbol-height');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeLineSeriesOutline(): void
@@ -1059,8 +1006,7 @@ public function testTypeLineSeriesOutline(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-width', '0.079cm');
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $expectedElement, 'svg:stroke-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-color', '#4a7ebb');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->setOutline($oOutline);
         $oLine->setSeries([$oSeries]);
@@ -1072,8 +1018,7 @@ public function testTypeLineSeriesOutline(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-width', $expectedWidthCm);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $expectedElement, 'svg:stroke-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-color', '#' . $oColor->getRGB());
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeLineSmooth(): void
@@ -1092,8 +1037,7 @@ public function testTypeLineSmooth(): void
         $this->assertZipFileExists('Object 1/content.xml');
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:interpolation');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
         $oLine->setIsSmooth(true);
@@ -1103,8 +1047,7 @@ public function testTypeLineSmooth(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:interpolation');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:interpolation', 'cubic-spline');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypePie(): void
@@ -1134,8 +1077,7 @@ public function testTypePie(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:reverse-direction', 'true');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypePie3D(): void
@@ -1165,8 +1107,7 @@ public function testTypePie3D(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:reverse-direction', 'true');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypePie3DExplosion(): void
@@ -1184,8 +1125,7 @@ public function testTypePie3DExplosion(): void
         $element = '/office:document-content/office:automatic-styles/style:style[@style:name=\'styleSeries0\'][@style:family=\'chart\']/style:chart-properties';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:pie-offset', $value);
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeRadar(): void
@@ -1210,8 +1150,7 @@ public function testTypeRadar(): void
         $element = '/office:document-content/office:automatic-styles/style:style[@style:name=\'styleAxisY\']/style:chart-properties';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:reverse-direction');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeRadarSeriesOutline(): void
@@ -1241,8 +1180,7 @@ public function testTypeRadarSeriesOutline(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-width', '0.079cm');
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $expectedElement, 'svg:stroke-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-color', '#4a7ebb');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $series->setOutline($outline);
         $radarChart->setSeries([$series]);
@@ -1254,8 +1192,7 @@ public function testTypeRadarSeriesOutline(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-width', $expectedWidthCm);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $expectedElement, 'svg:stroke-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-color', '#' . $color->getRGB());
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeScatter(): void
@@ -1270,8 +1207,7 @@ public function testTypeScatter(): void
         $element = '/office:document-content/office:body/office:chart/chart:chart';
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:class', 'chart:scatter');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeScatterMarker(): void
@@ -1298,8 +1234,7 @@ public function testTypeScatterMarker(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-width', $expectedSizeCm);
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-height', $expectedSizeCm);
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->getMarker()->setSymbol($expectedSymbol2);
         $oScatter->setSeries([$oSeries]);
@@ -1307,8 +1242,7 @@ public function testTypeScatterMarker(): void
 
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-name', 'horizontal-bar');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->getMarker()->setSymbol($expectedSymbol3);
         $oScatter->setSeries([$oSeries]);
@@ -1316,8 +1250,7 @@ public function testTypeScatterMarker(): void
 
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-name', 'circle');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->getMarker()->setSymbol($expectedSymbol4);
         $oScatter->setSeries([$oSeries]);
@@ -1325,8 +1258,7 @@ public function testTypeScatterMarker(): void
 
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'chart:symbol-name', 'arrow-up');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->getMarker()->setSymbol($expectedSymbol5);
         $oScatter->setSeries([$oSeries]);
@@ -1336,8 +1268,7 @@ public function testTypeScatterMarker(): void
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $expectedElement, 'chart:symbol-width');
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $expectedElement, 'chart:symbol-height');
 
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeScatterSeriesOutline(): void
@@ -1365,8 +1296,7 @@ public function testTypeScatterSeriesOutline(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-width', '0.079cm');
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $expectedElement, 'svg:stroke-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-color', '#4a7ebb');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $oSeries->setOutline($oOutline);
         $oScatter->setSeries([$oSeries]);
@@ -1378,8 +1308,7 @@ public function testTypeScatterSeriesOutline(): void
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-width', $expectedWidthCm);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $expectedElement, 'svg:stroke-color');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $expectedElement, 'svg:stroke-color', '#' . $oColor->getRGB());
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 
     public function testTypeScatterSmooth(): void
@@ -1398,8 +1327,7 @@ public function testTypeScatterSmooth(): void
         $this->assertZipFileExists('Object 1/content.xml');
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeNotExists('Object 1/content.xml', $element, 'chart:interpolation');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
 
         $this->resetPresentationFile();
         $scatter->setIsSmooth(true);
@@ -1409,7 +1337,6 @@ public function testTypeScatterSmooth(): void
         $this->assertZipXmlElementExists('Object 1/content.xml', $element);
         $this->assertZipXmlAttributeExists('Object 1/content.xml', $element, 'chart:interpolation');
         $this->assertZipXmlAttributeEquals('Object 1/content.xml', $element, 'chart:interpolation', 'cubic-spline');
-        // chart:title : Element chart failed to validate attributes
-        $this->assertIsSchemaOpenDocumentNotValid('1.2');
+        $this->assertIsSchemaOpenDocumentValid('1.2');
     }
 }
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentation/StylesTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentation/StylesTest.php
index 523087adfd..a6332b6382 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentation/StylesTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentation/StylesTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -59,7 +58,7 @@ public function testDocumentLayout(): void
     public function testCustomDocumentLayout(): void
     {
         $oDocumentLayout = new DocumentLayout();
-        $oDocumentLayout->setDocumentLayout(['cx' => rand(1, 100), 'cy' => rand(1, 100)]);
+        $oDocumentLayout->setDocumentLayout(['cx' => mt_rand(1, 100), 'cy' => mt_rand(1, 100)]);
         $this->oPresentation->setLayout($oDocumentLayout);
 
         $element = '/office:document-styles/office:automatic-styles/style:page-layout';
@@ -118,12 +117,14 @@ public function testStrokeDash(): void
                 case Border::DASH_SYSDOT:
                     $this->assertZipXmlAttributeExists('styles.xml', $element, 'draw:dots1');
                     $this->assertZipXmlAttributeExists('styles.xml', $element, 'draw:dots1-length');
+
                     break;
                 case Border::DASH_DASH:
                 case Border::DASH_LARGEDASH:
                 case Border::DASH_SYSDASH:
                     $this->assertZipXmlAttributeExists('styles.xml', $element, 'draw:dots2');
                     $this->assertZipXmlAttributeExists('styles.xml', $element, 'draw:dots2-length');
+
                     break;
                 case Border::DASH_DASHDOT:
                 case Border::DASH_LARGEDASHDOT:
@@ -134,6 +135,7 @@ public function testStrokeDash(): void
                     $this->assertZipXmlAttributeExists('styles.xml', $element, 'draw:dots1-length');
                     $this->assertZipXmlAttributeExists('styles.xml', $element, 'draw:dots2');
                     $this->assertZipXmlAttributeExists('styles.xml', $element, 'draw:dots2-length');
+
                     break;
             }
             $this->assertIsSchemaOpenDocumentValid('1.2');
diff --git a/tests/PhpPresentation/Tests/Writer/ODPresentationTest.php b/tests/PhpPresentation/Tests/Writer/ODPresentationTest.php
index ba8724708d..52f4e47c97 100644
--- a/tests/PhpPresentation/Tests/Writer/ODPresentationTest.php
+++ b/tests/PhpPresentation/Tests/Writer/ODPresentationTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -43,9 +42,9 @@ public function testConstruct(): void
         $this->oPresentation->getActiveSlide()->createDrawingShape();
         $object = new ODPresentation($this->oPresentation);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->getPhpPresentation());
-        $this->assertEquals('./', $object->getDiskCachingDirectory());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\HashTable', $object->getDrawingHashTable());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->getPhpPresentation());
+        self::assertEquals('./', $object->getDiskCachingDirectory());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\HashTable', $object->getDrawingHashTable());
     }
 
     /**
@@ -66,7 +65,7 @@ public function testSave(): void
         $object = new ODPresentation($this->oPresentation);
         $object->save($filename);
 
-        $this->assertTrue(file_exists($filename));
+        self::assertFileExists($filename);
 
         unlink($filename);
     }
@@ -89,11 +88,11 @@ public function testSaveEmpty(): void
     public function testSetGetUseDiskCaching(): void
     {
         $object = new ODPresentation($this->oPresentation);
-        $this->assertFalse($object->hasDiskCaching());
+        self::assertFalse($object->hasDiskCaching());
 
         $object->setUseDiskCaching(true, sys_get_temp_dir());
-        $this->assertTrue($object->hasDiskCaching());
-        $this->assertEquals(sys_get_temp_dir(), $object->getDiskCachingDirectory());
+        self::assertTrue($object->hasDiskCaching());
+        self::assertEquals(sys_get_temp_dir(), $object->getDiskCachingDirectory());
     }
 
     /**
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/CommentAuthorsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/CommentAuthorsTest.php
index 18552dbbc9..6fdf967f66 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/CommentAuthorsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/CommentAuthorsTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsAppTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsAppTest.php
index fc9ba5aefa..3ec8812f24 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsAppTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsAppTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCoreTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCoreTest.php
index 2f7f87732c..3a87a2613c 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCoreTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCoreTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCustomTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCustomTest.php
index 057b2b8397..098f72a339 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCustomTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsCustomTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsThumbnailTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsThumbnailTest.php
index c65bba64ec..cd29a97331 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsThumbnailTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/DocPropsThumbnailTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptChartsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptChartsTest.php
index aba15710fe..d2513a9289 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptChartsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptChartsTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -110,7 +109,7 @@ public function testChartIncludeSpreadsheet(): void
         $oLine->addSeries($oSeries);
         $oShape->getPlotArea()->setType($oLine);
 
-        $this->assertTrue($oShape->hasIncludedSpreadsheet());
+        self::assertTrue($oShape->hasIncludedSpreadsheet());
 
         $this->assertZipFileExists('ppt/charts/' . $oShape->getIndexedFilename());
         $this->assertZipFileExists('ppt/embeddings/' . $oShape->getIndexedFilename() . '.xlsx');
@@ -153,7 +152,7 @@ public function testChartIncludeSpreadsheet(): void
         $this->resetPresentationFile();
         $oShape->setIncludeSpreadsheet(false);
 
-        $this->assertFalse($oShape->hasIncludedSpreadsheet());
+        self::assertFalse($oShape->hasIncludedSpreadsheet());
 
         $this->assertZipFileExists('ppt/charts/' . $oShape->getIndexedFilename());
         $this->assertZipFileNotExists('ppt/charts/_rels/' . $oShape->getIndexedFilename() . '.rels');
@@ -199,11 +198,11 @@ public function testTitleVisibilityTrue(): void
         $oShape->getPlotArea()->setType($oLine);
 
         // Default
-        $this->assertTrue($oShape->getTitle()->isVisible());
+        self::assertTrue($oShape->getTitle()->isVisible());
 
         // Set Visible : TRUE
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Title', $oShape->getTitle()->setVisible(true));
-        $this->assertTrue($oShape->getTitle()->isVisible());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Title', $oShape->getTitle()->setVisible(true));
+        self::assertTrue($oShape->getTitle()->isVisible());
         $this->assertZipXmlElementExists('ppt/charts/' . $oShape->getIndexedFilename(), $element);
         $this->assertZipXmlAttributeEquals('ppt/charts/' . $oShape->getIndexedFilename(), $element, 'val', '0');
         $this->assertIsSchemaECMA376Valid();
@@ -219,8 +218,8 @@ public function testTitleVisibilityFalse(): void
         $oShape->getPlotArea()->setType($oLine);
 
         // Set Visible : FALSE
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Title', $oShape->getTitle()->setVisible(false));
-        $this->assertFalse($oShape->getTitle()->isVisible());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Title', $oShape->getTitle()->setVisible(false));
+        self::assertFalse($oShape->getTitle()->isVisible());
         $this->assertZipXmlElementExists('ppt/charts/' . $oShape->getIndexedFilename(), $element);
         $this->assertZipXmlAttributeEquals('ppt/charts/' . $oShape->getIndexedFilename(), $element, 'val', '1');
         $this->assertIsSchemaECMA376Valid();
@@ -334,12 +333,12 @@ public function testIsReversedOrder(): void
         $oShape->getPlotArea()->setType($oLine);
 
         // default
-        $this->assertFalse($oShape->getPlotArea()->getAxisX()->isReversedOrder());
+        self::assertFalse($oShape->getPlotArea()->getAxisX()->isReversedOrder());
         $this->assertZipXmlAttributeEquals('ppt/charts/' . $oShape->getIndexedFilename(), $element, 'val', 'minMax');
         $this->assertIsSchemaECMA376Valid();
 
         // reversed order
-        $this->assertInstanceOf(Axis::class, $oShape->getPlotArea()->getAxisX()->setIsReversedOrder(true));
+        self::assertInstanceOf(Axis::class, $oShape->getPlotArea()->getAxisX()->setIsReversedOrder(true));
         $this->resetPresentationFile();
 
         $this->assertZipXmlElementExists('ppt/charts/' . $oShape->getIndexedFilename(), $element);
@@ -347,7 +346,7 @@ public function testIsReversedOrder(): void
         $this->assertIsSchemaECMA376Valid();
 
         // reset reversed order
-        $this->assertInstanceOf(Axis::class, $oShape->getPlotArea()->getAxisX()->setIsReversedOrder(false));
+        self::assertInstanceOf(Axis::class, $oShape->getPlotArea()->getAxisX()->setIsReversedOrder(false));
         $this->resetPresentationFile();
 
         $this->assertZipXmlElementExists('ppt/charts/' . $oShape->getIndexedFilename(), $element);
@@ -538,7 +537,7 @@ public function testAxisTitleRotation(): void
         $this->assertZipXmlAttributeNotExists($pathShape, $element, 'rot');
 
         $this->resetPresentationFile();
-        $value = rand(0, 360);
+        $value = mt_rand(0, 360);
         $oShape->getPlotArea()->getAxisX()->setTitleRotation($value);
 
         $pathShape = 'ppt/charts/' . $oShape->getIndexedFilename();
@@ -558,8 +557,8 @@ public function testAxisVisibility(): void
         $oShape->getPlotArea()->setType($oLine);
 
         // Set Visible : FALSE
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Axis', $oShape->getPlotArea()->getAxisX()->setIsVisible(false));
-        $this->assertFalse($oShape->getPlotArea()->getAxisX()->isVisible());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Axis', $oShape->getPlotArea()->getAxisX()->setIsVisible(false));
+        self::assertFalse($oShape->getPlotArea()->getAxisX()->isVisible());
         $this->assertZipXmlElementExists('ppt/charts/' . $oShape->getIndexedFilename(), $element);
         $this->assertZipXmlAttributeEquals('ppt/charts/' . $oShape->getIndexedFilename(), $element, 'val', '1');
 
@@ -568,8 +567,8 @@ public function testAxisVisibility(): void
         $this->resetPresentationFile();
 
         // Set Visible : TRUE
-        $this->assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Axis', $oShape->getPlotArea()->getAxisX()->setIsVisible(true));
-        $this->assertTrue($oShape->getPlotArea()->getAxisX()->isVisible());
+        self::assertInstanceOf('PhpOffice\PhpPresentation\Shape\Chart\Axis', $oShape->getPlotArea()->getAxisX()->setIsVisible(true));
+        self::assertTrue($oShape->getPlotArea()->getAxisX()->isVisible());
         $this->assertZipXmlElementExists('ppt/charts/' . $oShape->getIndexedFilename(), $element);
         $this->assertZipXmlAttributeEquals('ppt/charts/' . $oShape->getIndexedFilename(), $element, 'val', '0');
 
@@ -777,7 +776,7 @@ public function testTypeBar3DSuperScript(): void
     public function testTypeDoughnut(): void
     {
         $randHoleSize = mt_rand(10, 90);
-        $randSeparator = chr(rand(ord('A'), ord('Z')));
+        $randSeparator = chr(mt_rand(ord('A'), ord('Z')));
 
         $oSlide = $this->oPresentation->getActiveSlide();
         $oShape = $oSlide->createChartShape();
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptCommentsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptCommentsTest.php
index 8c67c8ac76..d41b8d47d6 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptCommentsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptCommentsTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptMediaTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptMediaTest.php
index ca77f4d336..637851dd97 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptMediaTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptMediaTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresPropsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresPropsTest.php
index 6acf0e83be..8efef668ae 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresPropsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresPropsTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresentationTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresentationTest.php
index b3b02454a4..47ac1c3e43 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresentationTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptPresentationTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlideMastersTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlideMastersTest.php
index bc99f27c71..14cf1642b9 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlideMastersTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlideMastersTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -47,18 +46,19 @@ public function testWriteSlideMasterRelationships(): void
 
         $layouts = [new SlideLayout($slideMaster)];
 
-        $slideMaster->expects($this->once())
+        $slideMaster->expects(self::once())
             ->method('getAllSlideLayouts')
-            ->will($this->returnValue($layouts));
+            ->willReturn($layouts);
 
+        /** @var ArrayObject<int, ShapeDrawingFile> $collection */
         $collection = new ArrayObject();
         $collection[] = new ShapeDrawingFile();
         $collection[] = new ShapeDrawingFile();
         $collection[] = new ShapeDrawingFile();
 
-        $slideMaster->expects($this->exactly(2))
+        $slideMaster->expects(self::exactly(2))
             ->method('getShapeCollection')
-            ->will($this->returnValue($collection));
+            ->willReturn($collection);
 
         $data = $writer->writeSlideMasterRelationships($slideMaster);
 
@@ -69,13 +69,13 @@ public function testWriteSlideMasterRelationships(): void
         $xpath->registerNamespace('r', 'http://schemas.openxmlformats.org/package/2006/relationships');
         $list = $xpath->query('//r:Relationship');
 
-        $this->assertEquals(5, $list->length);
+        self::assertEquals(5, $list->length);
 
         foreach (range(0, 4) as $id) {
             /** @var DOMElement $domItem */
             $domItem = $list->item($id);
-            $this->assertInstanceOf(DOMElement::class, $domItem);
-            $this->assertEquals('rId' . (string) ($id + 1), $domItem->getAttribute('Id'));
+            self::assertInstanceOf(DOMElement::class, $domItem);
+            self::assertEquals('rId' . (string) ($id + 1), $domItem->getAttribute('Id'));
         }
     }
 }
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlidesTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlidesTest.php
index c1651a84c8..c8ad91423d 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlidesTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptSlidesTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,6 +35,7 @@
 use PhpOffice\PhpPresentation\Style\Fill;
 use PhpOffice\PhpPresentation\Style\Font;
 use PhpOffice\PhpPresentation\Tests\PhpPresentationTestCase;
+use ReflectionClass;
 
 class PptSlidesTest extends PhpPresentationTestCase
 {
@@ -1093,7 +1093,7 @@ public function testTransition(): void
         $this->assertZipXmlAttributeEquals('ppt/slides/slide1.xml', $element, 'spd', 'slow');
         $this->assertIsSchemaECMA376Valid();
 
-        $rcTransition = new \ReflectionClass('PhpOffice\PhpPresentation\Slide\Transition');
+        $rcTransition = new ReflectionClass('PhpOffice\PhpPresentation\Slide\Transition');
         $arrayConstants = $rcTransition->getConstants();
         foreach ($arrayConstants as $key => $value) {
             if (0 !== strpos($key, 'TRANSITION_')) {
@@ -1106,144 +1106,191 @@ public function testTransition(): void
             switch ($key) {
                 case 'TRANSITION_BLINDS_HORIZONTAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:blinds[@dir=\'horz\']');
+
                     break;
                 case 'TRANSITION_BLINDS_VERTICAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:blinds[@dir=\'vert\']');
+
                     break;
                 case 'TRANSITION_CHECKER_HORIZONTAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:checker[@dir=\'horz\']');
+
                     break;
                 case 'TRANSITION_CHECKER_VERTICAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:checker[@dir=\'vert\']');
+
                     break;
                 case 'TRANSITION_CIRCLE':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:circle');
+
                     break;
                 case 'TRANSITION_COMB_HORIZONTAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:comb[@dir=\'horz\']');
+
                     break;
                 case 'TRANSITION_COMB_VERTICAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:comb[@dir=\'vert\']');
+
                     break;
                 case 'TRANSITION_COVER_DOWN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cover[@dir=\'d\']');
+
                     break;
                 case 'TRANSITION_COVER_LEFT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cover[@dir=\'l\']');
+
                     break;
                 case 'TRANSITION_COVER_LEFT_DOWN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cover[@dir=\'ld\']');
+
                     break;
                 case 'TRANSITION_COVER_LEFT_UP':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cover[@dir=\'lu\']');
+
                     break;
                 case 'TRANSITION_COVER_RIGHT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cover[@dir=\'r\']');
+
                     break;
                 case 'TRANSITION_COVER_RIGHT_DOWN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cover[@dir=\'rd\']');
+
                     break;
                 case 'TRANSITION_COVER_RIGHT_UP':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cover[@dir=\'ru\']');
+
                     break;
                 case 'TRANSITION_COVER_UP':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cover[@dir=\'u\']');
+
                     break;
                 case 'TRANSITION_CUT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:cut');
+
                     break;
                 case 'TRANSITION_DIAMOND':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:diamond');
+
                     break;
                 case 'TRANSITION_DISSOLVE':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:dissolve');
+
                     break;
                 case 'TRANSITION_FADE':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:fade');
+
                     break;
                 case 'TRANSITION_NEWSFLASH':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:newsflash');
+
                     break;
                 case 'TRANSITION_PLUS':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:plus');
+
                     break;
                 case 'TRANSITION_PULL_DOWN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:pull[@dir=\'d\']');
+
                     break;
                 case 'TRANSITION_PULL_LEFT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:pull[@dir=\'l\']');
+
                     break;
                 case 'TRANSITION_PULL_RIGHT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:pull[@dir=\'r\']');
+
                     break;
                 case 'TRANSITION_PULL_UP':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:pull[@dir=\'u\']');
+
                     break;
                 case 'TRANSITION_PUSH_DOWN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:push[@dir=\'d\']');
+
                     break;
                 case 'TRANSITION_PUSH_LEFT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:push[@dir=\'l\']');
+
                     break;
                 case 'TRANSITION_PUSH_RIGHT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:push[@dir=\'r\']');
+
                     break;
                 case 'TRANSITION_PUSH_UP':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:push[@dir=\'u\']');
+
                     break;
                 case 'TRANSITION_RANDOM':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:random');
+
                     break;
                 case 'TRANSITION_RANDOMBAR_HORIZONTAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:randomBar[@dir=\'horz\']');
+
                     break;
                 case 'TRANSITION_RANDOMBAR_VERTICAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:randomBar[@dir=\'vert\']');
+
                     break;
                 case 'TRANSITION_SPLIT_IN_HORIZONTAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:split[@dir=\'in\'][@orient=\'horz\']');
+
                     break;
                 case 'TRANSITION_SPLIT_OUT_HORIZONTAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:split[@dir=\'out\'][@orient=\'horz\']');
+
                     break;
                 case 'TRANSITION_SPLIT_IN_VERTICAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:split[@dir=\'in\'][@orient=\'vert\']');
+
                     break;
                 case 'TRANSITION_SPLIT_OUT_VERTICAL':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:split[@dir=\'out\'][@orient=\'vert\']');
+
                     break;
                 case 'TRANSITION_STRIPS_LEFT_DOWN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:strips[@dir=\'ld\']');
+
                     break;
                 case 'TRANSITION_STRIPS_LEFT_UP':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:strips[@dir=\'lu\']');
+
                     break;
                 case 'TRANSITION_STRIPS_RIGHT_DOWN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:strips[@dir=\'rd\']');
+
                     break;
                 case 'TRANSITION_STRIPS_RIGHT_UP':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:strips[@dir=\'ru\']');
+
                     break;
                 case 'TRANSITION_WEDGE':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:wedge');
+
                     break;
                 case 'TRANSITION_WIPE_DOWN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:wipe[@dir=\'d\']');
+
                     break;
                 case 'TRANSITION_WIPE_LEFT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:wipe[@dir=\'l\']');
+
                     break;
                 case 'TRANSITION_WIPE_RIGHT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:wipe[@dir=\'r\']');
+
                     break;
                 case 'TRANSITION_WIPE_UP':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:wipe[@dir=\'u\']');
+
                     break;
                 case 'TRANSITION_ZOOM_IN':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:zoom[@dir=\'in\']');
+
                     break;
                 case 'TRANSITION_ZOOM_OUT':
                     $this->assertZipXmlElementExists('ppt/slides/slide1.xml', $element . '/p:zoom[@dir=\'out\']');
+
                     break;
             }
             $this->assertIsSchemaECMA376Valid();
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptTablePropsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptTablePropsTest.php
index dd4957b0d9..50322e7747 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptTablePropsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptTablePropsTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptViewPropsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptViewPropsTest.php
index a2bed9edfa..3bed78410e 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptViewPropsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/PptViewPropsTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/RelationshipsTest.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/RelationshipsTest.php
index 015e5464c1..e8dcbaec3b 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007/RelationshipsTest.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007/RelationshipsTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
diff --git a/tests/PhpPresentation/Tests/Writer/PowerPoint2007Test.php b/tests/PhpPresentation/Tests/Writer/PowerPoint2007Test.php
index e8b283b572..b51edfe28b 100644
--- a/tests/PhpPresentation/Tests/Writer/PowerPoint2007Test.php
+++ b/tests/PhpPresentation/Tests/Writer/PowerPoint2007Test.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -41,8 +40,8 @@ public function testConstruct(): void
     {
         $object = new PowerPoint2007($this->oPresentation);
 
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->getPhpPresentation());
-        $this->assertEquals('./', $object->getDiskCachingDirectory());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->getPhpPresentation());
+        self::assertEquals('./', $object->getDiskCachingDirectory());
     }
 
     /**
@@ -55,7 +54,7 @@ public function testSave(): void
         $object = new PowerPoint2007($this->oPresentation);
         $object->save($filename);
 
-        $this->assertTrue(file_exists($filename));
+        self::assertFileExists($filename);
 
         unlink($filename);
     }
@@ -78,15 +77,15 @@ public function testSaveEmptyException(): void
     public function testDiskCaching(): void
     {
         $object = new PowerPoint2007($this->oPresentation);
-        $this->assertFalse($object->hasDiskCaching());
+        self::assertFalse($object->hasDiskCaching());
 
         $object->setUseDiskCaching(true);
-        $this->assertTrue($object->hasDiskCaching());
-        $this->assertEquals('./', $object->getDiskCachingDirectory());
+        self::assertTrue($object->hasDiskCaching());
+        self::assertEquals('./', $object->getDiskCachingDirectory());
 
         $object->setUseDiskCaching(true, sys_get_temp_dir());
-        $this->assertTrue($object->hasDiskCaching());
-        $this->assertEquals(sys_get_temp_dir(), $object->getDiskCachingDirectory());
+        self::assertTrue($object->hasDiskCaching());
+        self::assertEquals(sys_get_temp_dir(), $object->getDiskCachingDirectory());
     }
 
     /**
diff --git a/tests/PhpPresentation/Tests/Writer/SerializedTest.php b/tests/PhpPresentation/Tests/Writer/SerializedTest.php
index 4d495d6d1b..77cc19a798 100644
--- a/tests/PhpPresentation/Tests/Writer/SerializedTest.php
+++ b/tests/PhpPresentation/Tests/Writer/SerializedTest.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -36,7 +35,7 @@ class SerializedTest extends TestCase
     public function testConstruct(): void
     {
         $object = new Serialized(new PhpPresentation());
-        $this->assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->getPhpPresentation());
+        self::assertInstanceOf('PhpOffice\\PhpPresentation\\PhpPresentation', $object->getPhpPresentation());
     }
 
     public function testSaveEmpty(): void
@@ -58,7 +57,7 @@ public function testSave(): void
         $object = new Serialized($oPhpPresentation);
         $object->save($file);
 
-        $this->assertFileExists($file);
+        self::assertFileExists($file);
     }
 
     public function testSaveNotExistingDir(): void
@@ -88,11 +87,11 @@ public function testSaveOverwriting(): void
         $oImage->setPath(PHPPRESENTATION_TESTS_BASE_DIR . DIRECTORY_SEPARATOR . 'resources' . DIRECTORY_SEPARATOR . 'images' . DIRECTORY_SEPARATOR . 'PhpPresentationLogo.png');
 
         $file = tempnam(sys_get_temp_dir(), 'PhpPresentation_Serialized');
-        file_put_contents($file, rand(1, 100));
+        file_put_contents($file, mt_rand(1, 100));
 
         $object = new Serialized($oPhpPresentation);
         $object->save($file);
 
-        $this->assertFileExists($file);
+        self::assertFileExists($file);
     }
 }
diff --git a/tests/PhpPresentation/Tests/_includes/PhpPresentationTestCase.php b/tests/PhpPresentation/Tests/_includes/PhpPresentationTestCase.php
index 77cba12ca8..2d3ebbe47a 100644
--- a/tests/PhpPresentation/Tests/_includes/PhpPresentationTestCase.php
+++ b/tests/PhpPresentation/Tests/_includes/PhpPresentationTestCase.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -29,11 +28,15 @@
 use PhpOffice\PhpPresentation\IOFactory;
 use PhpOffice\PhpPresentation\PhpPresentation;
 use PHPUnit\Framework\TestCase;
+use RecursiveDirectoryIterator;
+use RecursiveIteratorIterator;
+use SplFileInfo;
+use ZipArchive;
 
 class PhpPresentationTestCase extends TestCase
 {
     /**
-     * @var PhpPresentation|null
+     * @var null|PhpPresentation
      */
     protected $oPresentation;
 
@@ -55,19 +58,19 @@ class PhpPresentationTestCase extends TestCase
     /**
      * DOMDocument object.
      *
-     * @var DOMDocument|null
+     * @var null|DOMDocument
      */
     private $xmlDom;
 
     /**
-     * @var DOMXPath|null
+     * @var null|DOMXPath
      */
     private $xmlXPath;
 
     /**
      * File name.
      *
-     * @var string|null
+     * @var null|string
      */
     private $xmlFile;
 
@@ -204,7 +207,7 @@ protected function writePresentationFile(PhpPresentation $oPhpPresentation, $wri
         $xmlWriter = IOFactory::createWriter($oPhpPresentation, $writerName);
         $xmlWriter->save($this->filePath);
 
-        $zip = new \ZipArchive();
+        $zip = new ZipArchive();
         $res = $zip->open($this->filePath);
         if (true === $res) {
             $zip->extractTo($this->workDirectory);
@@ -406,10 +409,10 @@ public function assertIsSchemaECMA376Valid(): void
     {
         // validate all XML files
         $path = realpath($this->workDirectory . '/ppt');
-        $iterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($path));
+        $iterator = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path));
 
         foreach ($iterator as $file) {
-            /** @var \SplFileInfo $file */
+            /** @var SplFileInfo $file */
             if ('xml' !== $file->getExtension()) {
                 continue;
             }
@@ -433,10 +436,10 @@ public function assertIsSchemaOOXMLValid(): void
     {
         // validate all XML files
         $path = realpath($this->workDirectory . '/ppt');
-        $iterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($path));
+        $iterator = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path));
 
         foreach ($iterator as $file) {
-            /** @var \SplFileInfo $file */
+            /** @var SplFileInfo $file */
             if ('xml' !== $file->getExtension()) {
                 continue;
             }
@@ -479,11 +482,11 @@ public function assertIsSchemaOpenDocumentValid(string $version = '1.0', bool $t
 
         // validate all XML files
         $path = realpath($this->workDirectory);
-        $iterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($path));
+        $iterator = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($path));
 
         $isValid = true;
         foreach ($iterator as $file) {
-            /** @var \SplFileInfo $file */
+            /** @var SplFileInfo $file */
             if ('xml' !== $file->getExtension()) {
                 continue;
             }
@@ -530,15 +533,19 @@ protected function failXmlError(LibXMLError $error, string $fileName, string $so
         switch ($error->level) {
             case LIBXML_ERR_WARNING:
                 $errorType = 'warning';
+
                 break;
             case LIBXML_ERR_ERROR:
                 $errorType = 'error';
+
                 break;
             case LIBXML_ERR_FATAL:
                 $errorType = 'fatal';
+
                 break;
             default:
                 $errorType = 'Error';
+
                 break;
         }
         $errorLine = (int) $error->line;
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 88d30d03ca..8d83f9d836 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -12,7 +12,6 @@
  *
  * @see        https://github.com/PHPOffice/PHPPresentation
  *
- * @copyright   2009-2015 PHPPresentation contributors
  * @license     http://www.gnu.org/licenses/lgpl.txt LGPL version 3
  */
 
@@ -37,12 +36,12 @@
     }
 }
 
-spl_autoload_register(function ($class) {
+spl_autoload_register(function ($class): void {
     $class = ltrim($class, '\\');
     $prefix = 'PhpOffice\\PhpPresentation\\Tests';
     if (0 === strpos($class, $prefix)) {
         $class = str_replace('\\', DIRECTORY_SEPARATOR, $class);
-        $class = join(DIRECTORY_SEPARATOR, ['PhpPresentation', 'Tests', '_includes']) .
+        $class = implode(DIRECTORY_SEPARATOR, ['PhpPresentation', 'Tests', '_includes']) .
         substr($class, strlen($prefix));
         $file = __DIR__ . DIRECTORY_SEPARATOR . $class . '.php';
         if (file_exists($file)) {